Ottawa South (French: Ottawa-Sud) is a provincial electoral district (riding) in the Canadian province of Ontario, in the city of Ottawa.
The district was created in 1925 from part of Ottawa West.
Present day Ottawa South could be found in the riding of Russell prior to 1967.
After having been firmly conservative for the first 60 years, it has been in the hands of the Liberals without interruption since 1987.
McGuinty changed his mind however, and resigned on June 12 amid the "gas plant scandal".