Vlastimil Cerný (born April 7, 1963) is a former butterfly and freestyle swimmer, who competed for Canada at the 1988 Summer Olympics in Seoul, South Korea.
There he finished in 12th position in the 100-metre butterfly, and in ninth place with the men's 4x100-metre freestyle relay team.
In 1982, he, along with Miloslav Rolko, Tereza Vrtiskova and Josef Kuf (all swimmers), defected from Czechoslovakia following a meet in Sindelfingen, West Germany.