The following is a list of squads for each nation competing in men's football at the 2004 Summer Olympics in Athens. Each nation must submit a squad of 18 players, 15 of whom must be born on or after 1 January 1981, and three of whom can be older dispensation players.
See main article: Greece national under-23 football team. The following is the Greek squad in the men's football tournament of the 2004 Summer Olympics.[1]
Head coach: Stratos Apostolakis* Over-aged player.
See main article: Mali national football team. The following is the Malian squad in the men's football tournament of the 2004 Summer Olympics.[2]
Head coach: Cheick Oumar Kone* Over-aged player.
See main article: Mexico national under-23 football team. The following is the Mexican squad in the men's football tournament of the 2004 Summer Olympics.[3]
Head coach: 
Ricardo La Volpe* Over-aged player.
See main article: South Korea national under-23 football team. The following is the South Korean squad in the men's football tournament of the 2004 Summer Olympics.[4]
Head coach: Kim Ho-kon* Over-aged player.
See main article: Ghana national under-23 football team. The following is the Ghanaian squad in the men's football tournament of the 2004 Summer Olympics.[5]
Head coach: Mariano Barreto* Over-aged player.
See main article: Italy national under-23 football team. The following is the Italian squad in the men's football tournament of the 2004 Summer Olympics.[6]
Head coach: Claudio Gentile* Over-aged player.
See main article: Japan national under-23 football team. The following is the Japanese squad in the men's football tournament of the 2004 Summer Olympics.[7]
Head coach: Masakuni Yamamoto* Over-aged player.
See main article: Paraguay national under-23 football team. The following is the Paraguayan squad in the men's football tournament of the 2004 Summer Olympics.[8]
Head coach: Carlos Jara Saguier* Over-aged player.
See main article: Argentina national under-23 football team. The following is the Argentine squad in the men's football tournament of the 2004 Summer Olympics.[9]
Head coach: Marcelo Bielsa* Over-aged player.
See main article: Australia men's national under-23 soccer team. The following is the Australian squad in the men's football tournament of the 2004 Summer Olympics.[10]
Head coach: Frank Farina* Over-aged player.
See main article: Serbia and Montenegro national under-23 football team. The following is the Serbia and Montenegrin squad in the men's football tournament of the 2004 Summer Olympics.[11]
Head coach: Vladimir Petrović* Over-aged player.
See main article: Tunisia national football team. The following is the Tunisian squad in the men's football tournament of the 2004 Summer Olympics.[12]
Head coach: Khemais Labidi* Over-aged player.
See main article: Costa Rica national under-23 football team. The following is the Costa Rican squad in the men's football tournament of the 2004 Summer Olympics.[13]
Head coach: Rodrigo Kenton* Over-aged player.
See main article: Iraq national under-23 football team. The following is the Iraqi squad in the men's football tournament of the 2004 Summer Olympics.[14]
Head coach: Adnan Hamad* Over-aged player.
See main article: Morocco national under-23 football team. The following is the Moroccan squad in the men's football tournament of the 2004 Summer Olympics.[15]
Head coach: Mustapha Madih* Over-aged player.
See main article: Portugal Olympic football team. The following is the Portuguese squad in the men's football tournament of the 2004 Summer Olympics.[16]
Head coach: José Romão* Over-aged player.