Gregory Lee Walker (born October 6, 1959 in Douglas, Georgia) is a former power-hitting first baseman in Major League Baseball and the former hitting coach of the Chicago White Sox, the team for which he played all but the last 14 games of his career. As a player for 9 years, Walker hit 113 home runs and drove in 444 runs, while scoring 368 times. When he began his coaching career, he did so with the White Sox Triple-A club in Charlotte. In 1988 he had a seizure on the field at Comiskey Park during fielding practice. In 2003, he joined the parent club as hitting coach.