Jan Železný (born June 16, 1966 in Mladá Boleslav) is a Czech athlete, former world and Olympic champion and world record holder in javelin throw.

Železný won the gold both at the 1992, 1996 and 2000 Summer Olympic Games and Silver in the 1988 Olympics, to make him widely considered the greatest Javelin Thrower of all time. He has also won three World Championships, in 1993, 1995 and 2001.

Železný holds both the world record, at 98.48 m set in 1996, and the Olympic record, at 90.17 m set in the 2000 Summer Olympics. Železný is the only athlete to throw more than 97 m.

During his career he has had many great battles against the like of Steve Backley, Sergey Makarov , Boris Henry and Aki Parviainen .