Bishop's first role was in Grange Hill. He landed his second television role aged 16 and played young London ruffian Ben Quayle in the hit crime/ forensic drama Silent Witness. He also played Stupid Brian in My Family he appeared in 3 episodesIn 2005 he played comedian Dudley Moore on stage in Come Again, a drama charting Moore's turbulent relationship with Peter Cook, which debuted at the Assembly Rooms as part of the Edinburgh Fringe before transferring to The Venue in London's West End in March 2006. That same year, he could be seen in the Channel 4 British Comedy Awards 2006 winning comedy Star Stories. Bishop also worked for channel 4 on the satirical spoof documentary Being Tom Cruise from the series Star Stories first aired on Channel 4 on 2 August 2007, in which he portrays Tom Cruise.

The first edition of his new sketch series, The Kevin Bishop Show, commissioned by Channel 4 as a six part series, aired on 25 July 2008. The 2nd series began on 31 July 2009 Bishop describes the series as, "a rapid-fire sketch show based on the world of telly. It's set around a Sky box, with the idea that an unseen viewer is flicking channels quite regularly. That's a concept that allows us to get in and out of sketches really quickly."

Bishop gained attention during the 2008 British Comedy Awards. During the awards he heckled Ricky Gervais' pre-recorded acceptance speech VT and Katy Brand. During the ITV2 conclusion of the ceremony, Bishop threw bread sticks, a BCAs brochure and a bottle of pomegranate juice at the cast and producers of The Inbetweeners as they accepted the award for Best New Comedy. On Soccer AM in August 2009 he stated that throwing the bottles at the producers and actors was a joke and a bet that Bishop made with the producers themselves that he eventually won, but said he was not sober at the time. He also jokingly said that he had not received the £500 bet with producer Iain Morris.