Pak qualified as a lone male judoka for the North Korean squad in the men's extra-lightweight class (60 kg) at the 2004 Summer Olympics in Athens, by placing fifth and receiving a berth from the World Championships in Osaka, Japan. Facing a rematch against Tunisia's Anis Lounifi after his bronze medal defeat at the World Championships, Pak could not mount enough strength to topple his opponent with a harai goshi (sweeping hip throw), and thereby lost his opening bout by an ippon at one minute and twenty-eight seconds.