William Wardlaw Thompson (date of birth unknown - died 1917) was a South African ichthyologist and zoologist. It is known that he was educated at the South African College in Cape Town between 1858 and 1863 and that he obtained a post on the civil service of the Cape Colony in 1877 in the Railway Department as a temporary clerk. In January 1878 he secured a permanent post as a clerk in the Public Works Department, where he was promoted to First Clerk in 1882. In January 1885 he was transferred to the position of Chief records Clerk at the Crown Lands Office being promoted in July 1889 to first class clerk at the Department of Agriculture attaining the post of acting chief clerk there in November 1897. Prior to this he had taken and passed his Civil Service Law examinations and he also served with the Duke of Edinburgh's Own Volunteer Rifles in the Transkei during the 9th Frontier War in February to May 1879 and in Basutoland in September 1880 to March 1881 during the Basuto Gun War. Thompson was appointed to the Cape Colony's Fisheries Board in October 1897.