Thomas Alastair Sutherland Ogilvy ('Taso') Mathieson (25 July 1908, Glasgow – 12 October 1991, Vichy) was a British racing driver. Between 1930 and 1955, he entered more than 30 races, including multiple times the 24 Hours of Le Mans.
'Taso' Mathieson started racing in 1930, when he entered a race at Brooklands restricted to Lagondas. He established his first victory during an Easter Bank-Holiday BARC Open Meeting on 28 March 1932, driving a supercharged Officine Meccaniche. Over the next two years, he won three races in his Bugatti and broke the lap record for 2-litre cars at Snaefell Mountain Course on the Isle of Man, with an average speed of 72.15 mph (116.11 km/h).
Because of health problems, Mathieson was unable to enter any races from 1934 to 1937, so his Bugatti was driven a few times by Chris Staniland. In 1938 and 1939 he entered the 24 Hours of Le Mans, but both times retired before the finish.
Mathieson was one of the first, if not the first, Briton to race again in Continental Europe after World War II, racing an ex-Henry Birkin 3-litre Maserati in 1946. He later bought a 2-litre Frazer Nash Le Mans in which he scored a class victory in the 1950 24 Hours of Le Mans together with Richard Stoop. Mathieson also entered his English Racing Automobiles (ERA) for the 1950 British Grand Prix, so that Leslie Johnson could drive it. However, others say ERA was the entrant, because Johnson had purchased the car manufacturer three years before. He continued racing until 1955, mostly entering Grands Prix in France. When he was injured in a traffic or racing accident, he was forced to retire. After 25 years of racing, Mathieson concentrated on his writing and his collection of photographs, together with his wife Mila Parély, a French actress he had married in 1947. He wrote various authoritative books, including Grand Prix Racing 1906-1914, and wrote several articles in the French magazine Le Fanauto in 1979 and 1980.