Ramírez made his debut for Costa Rica in a February 1985 friendly match against El Salvador and earned a total of 75 caps, scoring 6 goals. He represented his country in 21 FIFA World Cup qualification matches and played at the 1990 FIFA World Cup held in Italy. He also played at the 1991 and 1997 UNCAF Nations Cups as well as at the 1991 CONCACAF Gold Cup and the 1997 Copa América in Bolivia.