Leonardus Quirinus Machutus ("Leo") van Vliet (born 15 November 1955) was a professional racing cyclist from 1978 to 1986. He came in 40th in the road race at the 1976 Summer Olympics in Montreal, Canada.
Van Vliet's biggest success was the 1983 Gent–Wevelgem. He also won the seventh stage of the 1979 Tour de France. After his career, he became the director of the only Dutch cycling classic, the Amstel Gold Race. He is not related to another Dutch cyclist of the 1980s, Teun van Vliet.