My fundamental interest, I suppose, is signs and proofs of other powers that lie hidden in us all; the extension, in other words, of human faculty. So many of my stories, therefore, deal with extension of consciousness; speculative and imaginative treatment of possibilities outside our normal range of consciousness. ... Also, all that happens in our universe is natural; under Law; but an extension of our so limited normal consciousness can reveal new, extra-ordinary powers etc., and the word "supernatural" seems the best word for treating these in fiction. I believe it possible for our consciousness to change and grow, and that with this change we may become aware of a new universe. A "change" in consciousness, in its type, I mean, is something more than a mere extension of what we already possess and know.

• H. P. Lovecraft included Blackwood as one of the "Modern Masters" in the chapter of that name in Supernatural Horror in Literature.
• Peter Penzoldt devotes the final chapter of The Supernatural in Fiction (1952) to an analysis of Blackwood's work, and the book is dedicated "with deep admiration and gratitude, to Algernon Blackwood, the greatest of them all".
• There is an extensive critical analysis of Blackwood's work in Jack Sullivan's book Elegant Nightmares: The English Ghost Story From Le Fanu to Blackwood (1978).
• There is a critical essay on Blackwood's work in S. T. Joshi's The Weird Tale (1990).
• The plot of Caitlin R. Kiernan's novel Threshold (2001) draws upon Blackwood's "The Willows", which is quoted several times in the book. Kiernan has cited Blackwood as an important influence on her writing.
• In The Books in My Life, Henry Miller chose Blackwood's The Bright Messenger as "the most extraordinary novel on psychoanalysis, one that dwarfs the subject."

Novels

• Jimbo: A Fantasy (1909a)
• The Education of Uncle Paul (1909b)
• The Human Chord (1910)
• The Centaur (1911)
• A Prisoner in Fairyland (1913); sequel to The Education of Uncle Paul
• The Extra Day (1915)
• Julius LeVallon (1916a)
• The Wave (1916b)
• The Promise of Air (1918a)
• The Garden of Survival (1918b)
• The Bright Messenger (1921); sequel to Julius LeVallon
• Dudley & Gilderoy: A Nonsense (1929)

• Sambo and Snitch (1927)
• The Fruit Stoners: Being the Adventures of Maria Among the Fruit Stoners (1934)

Plays

• The Starlight Express (1915), coauthored with Violet Pearn; incidental music by Edward Elgar; based on Blackwood's 1913 novel A Prisoner in Fairyland
• The Crossing (1920a), coauthored with Bertram Forsyth; based on Blackwood's 1913 short story "Transition"
• Through the Crack (1920b), coauthored with Violet Pearn; based on Blackwood's 1909 novel The Education of Uncle Paul and 1915 novel The Extra Day
• White Magic (1921a), coauthored with Bertram Forsyth
• The Halfway House (1921b), coauthored with Elaine Ainley
• Max Hensig (1929), coauthored with Frederick Kinsey Peile; based on Blackwood's 1907 short story "Max Hensig ... Bacteriologist and Murderer"

Short fiction collections

• The Empty House and Other Ghost Stories (1906); original collection
• The Listener and Other Stories (1907); original collection
• John Silence (1908); original collection; reprinted with added preface, 1942
• The Lost Valley and Other Stories (1910); original collection
• Pan's Garden: a Volume of Nature Stories (1912); original collection
• Ten Minute Stories (1914a); original collection
• Incredible Adventures (1914b); original collection
• Day and Night Stories (1917); original collection
• Wolves of God, and Other Fey Stories (1921), honorarily coauthored with Wilfred Wilson; original collection
• Tongues of Fire and Other Sketches (1924); original collection
• Ancient Sorceries and Other Tales (1927a); selections from previous Blackwood collections, and pre-publication abridgment of 1932's planned The Willows and Other Queer Tales
• The Dance of Death and Other Tales (1927b); selections from previous Blackwood collections; reprinted as 1963's The Dance of Death and Other Stories
• Strange Stories (1929); selections from previous Blackwood collections
• Short Stories of To-Day & Yesterday (1930); selections from previous Blackwood collections
• The Willows and Other Queer Tales (1932); selected by G. F. Maine from previous Blackwood collections
• Shocks (1935); original collection
• The Tales of Algernon Blackwood (1938); selections from previous Blackwood collections, with a new preface by Blackwood
• Selected Tales of Algernon Blackwood (1942); selections from previous Blackwood collections (not to be mistaken for the identical title to a 1964 Blackwood collection)
• Selected Short Stories of Algernon Blackwood (1945); selections from previous Blackwood collections
• The Doll and One Other (1946); original collection
• Tales of the Uncanny and Supernatural (1949); selections from previous Blackwood collections
• In the Realm of Terror (1957); selections from previous Blackwood collections
• The Dance of Death and Other Stories (1963); reprint of 1927's The Dance of Death and Other Tales
• Selected Tales of Algernon Blackwood (1964); selections from previous Blackwood collections (not to be mistaken for the identical title to a 1942 Blackwood collection)
• Tales of the Mysterious and Macabre (1967); selections from previous Blackwood collections
• Ancient Sorceries and Other Stories (1968); selections from previous Blackwood collections
• Best Ghost Stories of Algernon Blackwood (1973), selected and introduced by Everett F. Bleiler; selections from previous Blackwood collections; includes Blackwood's own preface to 1938's The Tales of Algernon Blackwood
• The Best Supernatural Tales of Algernon Blackwood (1973); selected and introduced by Felix Morrow; selections from 1929's Strange Stories
• Tales of Terror and Darkness (1977); selections from previous Blackwood collections
• Tales of the Supernatural (1983); selected and introduced by Mike Ashley; selections from previous Blackwood collections
• The Magic Mirror (1989); selected, introduced, and notes by Mike Ashley; original collection
• The Complete John Silence Stories (1997); selected and introduced by S. T. Joshi; reprint of 1908's John Silence (without the preface to the 1942 reprint) and the one remaining John Silence story, "A Victim of Higher Space"
• Ancient Sorceries and Other Weird Stories (2002); selected, introduced, and notes by S. T. Joshi; selections from previous Blackwood collections
• Algernon Blackwood's Canadian Tales of Terror (2004); selected, introduced, with notes by John Robert Colombo; eight stories of special Canadian interest plus information on the author's years in Canada

Select short story synopses

• "A Haunted Island" (1899)
• :To prepare for his professional examinations, a young man remains after the other summer visitors to a lake in the Canadian wilderness have gone, but soon he experiences a terrifying vision of himself hunted and murdered.
• "Smith: An Episode in a Lodging House" (1906)
• :A man and his strange neighbor's paths meet more often than he would like in this story of a man delving into secrets he should not know.
• "The Willows" (1907)
• :Perhaps Blackwood's most celebrated story, this was influenced heavily by his own trips up the Danube. Two campers find themselves staying in an eerie locale, impinged on by another dimension. H. P. Lovecraft considered this the finest supernatural tale in English literature.
• "The Insanity of Jones" (1907)
• :A reincarnation story based around the correcting of past wrongs by revenge.
• "Ancient Sorceries" (1908)
• :A tourist returning from a trip becomes too enchanted with a strange French town and its people to leave. He is slowly drawn more and more into their realm of secrets and talk of ancient memories.
• "The Wendigo" (1910)
• :Another camper tale, this time set in the Canadian wilderness. A hunting party separates to track moose, and one member is abducted by the Wendigo of legend. Robert Aickman regarded this as "one of the (possibly) six great masterpieces in the field".
• "The Glamour of the Snow" (1911)
• :A traveller meets a strange woman late one night at a ski resort and spends the rest of his vacation searching for her, so that they can have one last moment together. He almost gets his wish....
• "The Man Whom the Trees Loved" (1912)
• :A wife is powerless to save her husband from the nature he loves and its ever growing influence on his life.
• "The Regeneration of Lord Ernie" (1914)
• :A listless young aristocrat is transformed into a firebrand through witnessing a mystical ceremony.
• "The Damned" (1914)
• :A highly original haunted house tale in which the haunting results from the intolerant religious beliefs of a series of previous residents.
• "A Descent into Egypt" (1914)
• :A long, carefully constructed story in which a man's soul is gradually subsumed into eternity.
• "The Man Who Found Out" (1921)
• :A researcher goes on an expedition to find "The Tablets of the Gods" which have plagued his dreams since his boyhood. He finds them, and the horrible truth of humanity's true purpose in the universe.

Short fiction

• "A Mysterious House" (1889)
• "The Story of Karl Ott" (1896)
• "A Haunted Island" (1899)
• "A Case of Eavesdropping" (1900)
• "The Last Egg in the Nest" (1902)
• "The House of the Past" (1904a)
• "Testing His Courage ... The Story of a Quaint Device" (1904b)
• "How Garnier Broke the Log-Jam" (1904c)
• "The Empty House" (1906a)
• "Keeping His Promise" (1906b)
• "With Intent to Steal" (1906c)
• "The Wood of the Dead" (1906d)
• "Smith: An Episode in a Lodging House" (1906e)
• "A Suspicious Gift" (1906f)
• "The Strange Adventures of a Private Secretary in New York" (1906g)
• "Skeleton Lake: An Episode in Camp" (1906h)
• "The Listener" (1907a)
• "Max Hensig ... Bacteriologist and Murderer" (1907b)
• "The Willows" (1907c)
• "The Insanity of Jones" (1907d)
• "The Dance of Death" (1907e)
• "The Old Man of Visions" (1907f)
• "May Day Eve" (1907g)
• "Miss Slumbubble ... and Claustrophobia" (1907h)
• "The Woman's Ghost Story" (1907i)
• "A Psychical Invasion" (1908a)
• "Ancient Sorceries" (1908b)
• "The Nemesis of Fire" (1908c)
• "Secret Worship" (1908d)
• "The Camp of the Dog" (1908e)
• "The Secret" (1908f)
• "The Kit-Bag" (1908g)
• "Stodgman's Opportunity" (1908h)
• "The Story of Mr. Popkiss Told" (1908i)
• "Entrance and Exit" (1909a)
• "You May Telephone From Here" (1909b)
• "The Invitation" (1909c)
• "The Lease" (1909d)
• "Faith Cure on the Channel" (1909e)
• "Carlton's Drive" (1909f)
• "The Laying of a Red-Haired Ghost" (1909g)
• "Up and Down" (1909h)
• "The Man Who Played upon the Leaf" (1909i)
• "The Terror of the Twins" (1909j)
• "The Strange Disappearance of a Baronet" (1909k)
• "The Occupant of the Room" (1909l)
• "The South Wind" (1910a)
• "If the Cap Fits ..." (1910b)
• "Perspective" (1910c)
• "Special Delivery" (1910d)
• "The Lost Valley" (1910e)
• "The Wendigo" (1910f)
• "Old Clothes" (1910g)
• "The Man From the 'Gods'" (1910h)
• "The Price of Wiggins's Orgy" (1910i)
• "The Eccentricity of Simon Parnacute" (1910j)
• "The Message of the Clock" (1910k)
• "The Sea Fit" (1910l)
• "The Singular Death of Morton" (1910m)
• "Imagination" (1910n)
• "The Empty Sleeve" (1911a)
• "The Deferred Appointment" (1911b)
• "The Impulse" (1911c)
• "The Prayer" (1911d)
• "The Return" (1911e)
• "Two in One" (1911f)
• "Accessory Before the Fact" (1911g)
• "Clairvoyance" (1911h)
• "Dream Trespass" (1911i)
• "News vs Nourishment" (1911j)
• "The Glamour of the Snow" (1911k)
• "The Transfer" (1911l)
• "The Messenger" (1911m)
• "In a Jura Village" (1911n); subsequently incorporated into Blackwood's 1913 novel A Prisoner in Fairyland
• "The Golden Fly" (1911o)
• "The Heath Fire" (1912a)
• "The Biter Bit" (1912b)
• "The Destruction of Smith" (1912c)
• "The Man Whom the Trees Loved" (1912d)
• "Egyptian Antiquities" (1912e)
• "The Attic" (1912f)
• "The Whisperers" (1912g)
• "The Second Generation" (1912h)
• "Ancient Lights" (1912i)
• "Sand" (1912j)
• "The Temptation of the Clay" (1912k)
• "The Goblin's Collection" (1912l)
• "Let Not the Sun ..." (1912m)
• "La Mauvaise Riche" (1912n)
• "The Man Who Found Out" (1912o)
• "Wayfarers" (1912p)
• "The Sacrifice" (1913a)
• "Her Birthday" (1913b)
• "Violence" (1913c)
• "Jimbo's Longest Day" (1913d)
• "Who Was She?" (1913e)
• "The Barmecide Feast" (1913f)
• "The Kiss of a Psychologist" (1913g)
• "H.S.H." (1913h)
• "The Story Hour" (1913i); subsequently incorporated into Blackwood's 1915 novel The Extra Day
• "The Tradition" (1913j)
• "Transition" (1913k)
• "A Desert Episode" (1914a)
• "What Nobody Understands" (1914b); subsequently incorporated into Blackwood's 1915 novel The Extra Day
• "Maria" (1914c); subsequently incorporated into Blackwood's 1915 novel The Extra Day
• "By Water" (1914d)
• "A Bit of Wood" (1914e)
• "The Night Wind" (1914f)
• "The Falling Glass" (1914g)
• "Breakfast Honey" (1914h)
• "The Philosopher" (1914i)
• "The Daisy World" (1914j); subsequently incorporated into Blackwood's 1915 novel The Extra Day

• "The Wings of Horus" (1914k)
• "The Regeneration of Lord Ernie" (1914l)
• "The Damned" (1914m)
• "A Descent into Egypt" (1914n)
• "A Victim of Higher Space" (1914o)
• "Non-Human" (1914p)
• "An Egyptian Hornet" (1915a)
• "The God" (1915b)
• "The Soldier's Visitor" (1915c)
• "The Paper Man" (1915d)
• "The Other Wing" (1915e)
• "Cain's Atonement" (1915f)
• "The Celestial Motor-'Bus" (1915g)
• "The Exiled Gods" (1916a); thereafter reprinted as "Initiation" (commencing 1917)
• "Proportion" (1916b)
• "Camping Out" (1916c)
• "The Tryst" (1917a)
• "The Touch of Pan" (1917b)
• "Laughter of Courage" (1917c)
• "The Memory of Beauty" (1918a)
• "S.O.S." (1918b)
• "The Little Beggar" (1919a)
• "Picking Fir-Cones" (1919b)
• "The Perfect Poseur" (1919c)
• "The World-Dream of McCallister" (1919d)
• "Alexander Alexander" (1919e)
• "Wireless Confusion" (1919f)
• "The Other Woman" (1919g)
• "The Decoy" (1919h)
• "The Call" (1919i)
• "First Hate" (1920a)
• "Chinese Magic" (1920b)
• "Running Wolf" (1920c)
• "Onanonanon" (1921a)
• "Confession" (1921b)
• "The Valley of the Beasts" (1921c)
• "The Wolves of God" (1921d)
• "The Tarn of Sacrifice" (1921e)
• "Egyptian Sorcery" (1921f)
• "The Lane That Ran East and West" (1921g)
• "Vengeance Is Mine" (1921h)
• "The Olive" (1921i)
• "Changing 'Ats" (1921j)
• "Nephelé" (1921k)
• "Genius" (1922a)
• "Lost!" (1922b)
• "Tongues of Fire" (1923a)
• "The Pikestaffe Case" (1923b)
• "The Man Who Was Milligan" (1923c)
• "A Man of Earth" (1924a)
• "The Open Window" (1924b)
• "Malahide and Forden" (1924c)
• "Playing Catch" (1924d)
• "A Continuous Performance" (1924e)
• "Petershin and Mr. Snide" (1924f)
• "The Impulse" (1924g)
• "Full Circle" (1925a)
• "Hands of Death" (1925b)
• "Chemical (1926)
• "The Crossword Alien" (1927a)
• "The Stranger" (1927b)
• "The Land of Green Ginger" (1927c)
• "Dr. Feldman" (1928)
• "The Adventure of Tornado Smith" (1929)
• "Mr. Bunciman at the Zoo" (1930a)
• "Shocks" (1930b)
• "The Survivors" (1930c)
• "The Man Who Lived Backwards" (1930d)
• "Revenge" (1930e)
• "The Colonel's Ring" (1930f)
• "The Fire Body" (1931a)
• "A Threefold Cord..." (1931b)
• "The Blackmailers" (1935a)
• "Elsewhere and Otherwise" (1935b)
• "Adventures of Miss de Fontenay" (1935c)
• "At a Mayfair Luncheon" (1936a)
• "That Mrs. Winslow" (1936b)
• "The Man-Eater" (1937a)
• "By Proxy" (1937b)
• "The Reformation of St. Jules" (1937c); subsequently reprinted as "The Voice" (1989)
• "The Magic Mirror" (1938)
• "King's Evidence" (1941); Blackwood's own revision and condensation of his 1921 story "Confession"
• "The Doll" (1946a)
• "The Trod" (1946b)
• "Roman Remains" (1948)
• "The Wig" (1989a); posthumously published manuscript
• "Lock Your Door" (1989b); posthumously published manuscript
• "Wishful Thinking" (1989c); posthumously published manuscript

• "Toby's Birthday Presents" (1926)
• "Mr. Cupboard, or The Furniture's Holiday" (1927a)
• "The Water Performance" (1927b)
• "When Nick Dressed Up" (1928a)
• "The Chocolate Cigarettes" (1928b)
• "My Underground" (1929)
• The Graceless Pair, a serial of six magazine stories constituting a prequel to Blackwood's 1929 novel Dudley & Gilderoy: A Nonsense:
• "The Saving of Colonelsirarthur" (1930a)
• "French and Italian" (1930b)
• "Burglars" (1930c)
• "'Anyopedoctor? Abaslesboches! Etc.'" (1930d)
• "The Fish Pond" (1930e)
• "The Afternoon Call" (1930f)
• "The Parrot and the ... Cat!" (1930g); prequel to Blackwood's 1929 novel Dudley & Gilderoy: A Nonsense and to his 1930 serial The Graceless Pair
• "The Italian Conjuror" (1931)
• "Maria (of England) in the Rain" (1932)
• "Sergeant Poppett and Policeman James" (1933a)
• "What the Black Chow Saw" (1933b)
• "The Fruit Stoners" (1934); linked to, but not part of, Blackwood's 1934 novel The Fruit Stoners: Being the Adventures of Maria Among the Fruit Stoners
• "How the Circus Came to Tea" (1935)
• "Eliza Among the Chimney Sweeps" (1950)

Nonfiction

• Episodes Before Thirty (1923); reissued in 1950 with newly incorporated photographic plates and a brief prefatory "Author's Note".