Ramón Abraham Castro (born March 1, 1976 in Vega Baja, Puerto Rico) is a Major League Baseball catcher for the Chicago White Sox.

On June 2 1994 Castro was selected by the Houston Astros in the first round (17th overall pick) of the Major League Baseball draft, becoming the first Puerto Rican to ever be drafted in the first round. He was traded to the Florida Marlins in 1998 for relief pitcher Jay Powell.

Castro made his major league debut on August 27, 1999 in a game against the Houston Astros. He spent 1999 and 2000 competing with Mike Redmond for playing time and, when Charles Johnson arrived in Florida, Castro spent most of the 2001 season in the minor leagues. In 2002 he was back in the majors but as a third option and, in 2003, he played behind Iván Rodríguez as the Marlins won the 2003 World Series. However, Castro did not appear in the series. In 2004 Rodríguez was gone, giving Castro his first opportunity as a starter but a .135 batting average and an early-June season-ending injury finished his time in Florida. Paul Lo Duca finished out the Marlins' catching duties for 2004. The Marlins released Castro in October 2004.