1981 South American Championships – Singles

José Luis Clerc was the defending champion but did not compete that year.

Ivan Lendl won in the final 6–2, 6–2 against Guillermo Vilas.

Seeds
A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated.


 * 1)  Ivan Lendl (champion)
 * 2) 🇦🇷 Guillermo Vilas (final)
 * 3)  Víctor Pecci (first round)
 * 4)  Hans Gildemeister (second round)
 * 5)  Rolf Gehring (quarterfinals)
 * 6)  Jose Luis Damiani (second round)
 * 7) 🇪🇸 José Higueras (second round)
 * 8) 🇪🇨 Andrés Gómez (quarterfinals)