Triska fell off the bridge on Saturday and was rescued from the Vltava river by two tourists on a boat but died in hospital on Sunday, according to the website of the DNES daily.
Czech firefighters said he had jumped while emergency services said the fall was accidental.
Triska, who played the sniper who shot Larry Flynt in compatriot Milos Forman’s 1996 “The People vs Larry Flynt”, and the Russian gunman in John Frankenheimer’s “Ronin” in 1998, was born in the former Czechoslovakia in 1936.
A close friend of former Czech anti-Communist dissident and later president Vaclav Havel, the popular actor emigrated from Communist Czechoslovakia to the United States in 1977.
His films were then banned from local cinemas and TV screens until the fall of communism in 1989.
Besides his Hollywood roles, Triska starred in several Czech films after 1989, including the Oscar-nominated “The Elementary School” in 1991.