The 2004 CONMEBOL Pre-Olympic Tournament began on 7 January 2004, and is the 12th CONMEBOL Pre-Olympic Tournament. This was the 4th tournament is open to players under the age of 23 without any other restriction. There is no qualification stage and all 10 member of CONMEBOL automatic qualified. The winner and the runner-up qualified for 2004 Summer Olympics. Players born on or after 1 January 1981 were eligible to play in this competition.

The men's football tournament at the 2004 Summer Olympics was held in Athens and four other cities in Greece from 11 to 28 August. The tournament featured 16 men's national teams from the six continental confederations. The 16 teams were drawn into four groups of four, in which each team would play each of the others once. At the end of the group stage, the top two teams advanced to the knockout stage, beginning with the quarter-finals and culminating with the final at Athens' Olympic Stadium on 28 August 2004.