José Guillermo Rivera Escobar (born November 25, 1969) is a retired Salvadoran professional football player.
Nicknamed Memo, Rivera came through the youth ranks at FAS, where he would stay for over a decade and win two league titles. In 1999, he moved abroad for a stint at Guatemalan side USAC. He returned to El Salvador to play for Salvadoran second division side Isidro Metapán alongside fellow international William Renderos Iraheta and finished his career at Once Lobos.
Rivera made his debut for El Salvador in 1988 and has earned a total of 74 caps, scoring 15 goals. He has represented his country in 22 FIFA World Cup qualification matches and played at the 1991, 1993, 1995 and 1999 UNCAF Nations Cups and was a non-playing squad member at the 1996 CONCACAF Gold Cup but did play at the 1998 CONCACAF Gold Cup.
His final international game was an August 2000 FIFA World Cup qualification match against Jamaica.
Rivera is married and has two children.