The 1999 South American Youth Championship (Sudamericana sub-20) is a football competition contested by all ten U-20 national football teams of CONMEBOL. The tournament was held in Argentina between 5 and 25 January 1999, the 23rd time the competition had been held and the 2nd to take place in the country. Argentina finished undefeated, winning their 3rd trophy.
The teams are separated in two groups of five, and each team plays four matches in a pure round-robin stage. The three top competitors advance to a single final group of six, wherein each team plays five matches. The top four teams in the final group qualify to the 1999 FIFA World Youth Championship.
For a list of all the squads in the final tournament, see 1999 South American Youth Championship squads.
The following teams entered the tournament:
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The four best performing teams qualified for the 1999 FIFA World Youth Championship.