Colony in Space is the fourth serial of the eighth season of the British science fiction television series Doctor Who, which was first broadcast in six weekly parts on BBC1 from 10 April to 15 May 1971.

The eighth season of British science fiction television series Doctor Who began on 2 January 1971 with Terror of the Autons and ended with The Dæmons featuring Jon Pertwee as the Third Doctor. This is the second of five series which Barry Letts produced consecutively and Terrance Dicks was the script editor.