The 3rd Lo Nuestro Awards ceremony, presented by Univision honoring the best Latin music of 1990 and 1991 took place on May 23, 1991, at a live presentation held at the James L. Knight Center in Miami, Florida. The ceremony was broadcast in the United States and Latin America by Univision.

The Lo Nuestro Award for Pop Song of the Year is an honor presented annually by American television network Univision at the Lo Nuestro Awards. The accolade was established to recognize the most talented performers of Latin music. The nominees and winners were originally selected by a voting poll conducted among program directors of Spanish-language radio stations in the United States and also based on chart performance on Billboard Latin music charts, with the results being tabulated and certified by the accounting firm Deloitte. However, since 2004, the winners are selected through an online survey. The trophy awarded is shaped in the form of a treble clef.