Otten was born in Amsterdam as the son of the musicians Marijke Ferguson and Kees Otten. He spent his youth in the Rivierenbuurt (Rivers Area) in Amsterdam and in Laren.

He grew up in an atmosphere of moral libertinism. His nonfiction is in part a reflection upon that atmosphere and a polemic with the philosophy behind that atmosphere. He published his first book of poetry in 1973. He has published essays and fiction about euthanasia and played a role in the euthanasia debate in the Netherlands by criticizing the arguments in favour of euthanasia and the freedom of choice in matters of one's own life and death.

In 1999 he published an essay Het wonder van de losse olifanten, een rede tot de ontwikkelden onder de verachters van de christelijke religie (The miracle of the solitary elephants. Lecture addressed to the cultivated among the despisers of the Christian religion) in which he examined the arguments pro and contra christian belief. This 'lecture' followed upon his conversion to Roman Catholicism. His wife Vonne van der Meer is a Roman Catholic convert too.

Some of his books are translated in Italian, German, French and Swedish.

• 1972 - Reina Prinsen Geerligsprijs - Een zwaluw vol zaagsel
• 1981 - Herman Gorterprijs -Ik zoek het hier
• 1992 - Jan Campertprijs - Paviljoenen
• 1994 - Busken Huetprijs - De letterpiloot
• 1999 - Constantijn Huygens Prize - collected works
• 2005 - Libris Literatuur Prijs - Specht en zoon

In 2007 Otten received an honorary degree in theology from Utrecht University.

Willem Jan OttenWillem Jan Otten