Juan Castillo Brayas (born January 25, 1962) is a former professional baseball player. He played all or part of four seasons in Major League Baseball from 1986 until 1989, all for the Milwaukee Brewers. His primary position was second base, but he also played a good deal at third base and shortstop. Castillo has one daughter and three sons and lives in Miami, Florida, with his wife and two youngest sons.