The 1991 UNCAF Nations Cup was the inaugural UNCAF Nations Cup, the Central American championship for men's national association football teams. It was organized by the Unión Centroamericana de Fútbol or UNCAF, and it took place in Costa Rica from May 26 to June 2, 1991. All matches were played in the Costa Rican capital, San José at the Estadio Nacional. The top two teams, apart from Costa Rica, go on to participate in the 1991 CONCACAF Gold Cup. Costa Rica were given a bye due to their performance at the 1990 FIFA World Cup.