Thomas Harold Harmon (born December 16, 1948, at Lubbock, Texas) is an American baseball coach and a former minor league catcher and manager and Major League coach. He was assistant coach of the University of Texas Longhorns men's varsity baseball team from 1989 to 2012.^[1]

As a player, Harmon batted left-handed and threw right-handed; he stood 5 ft 11 in (1.80 m) tall and weighed 185 lb (84 kg). He graduated from Eastern Hills High School of Fort Worth, Texas, and The University of Texas at Austin with a degree in marketing.^[2] Harmon was a first-round, secondary phase selection of the Kansas City Royals in the June 1970 Major League Baseball draft, and broke into professional baseball at the advanced Double-A level, with the Elmira Pioneers of the Eastern League. In 1972, while a member of the Jacksonville Suns, he set a Southern League record with six hits in an extra-inning game — although he batted only .201 in 209 at bats for Jacksonville that season.^[2]

Although he never reached the Major Leagues, Harmon spent all or parts of seven seasons at the Triple-A level, and he finished his career in the St. Louis Cardinals and Philadelphia Phillies organizations, batting .254 in 649 games played with 12 home runs and 179 runs batted in.^[3] He then coached and managed in the Phillies' organization, where he won the 1979 Northwest League championship, from 1978 through 1981. In 1982, he spent a year at the major-league level as bullpen coach on the staff of Chicago Cubs manager Lee Elia. Like Harmon, Elia was a veteran of the Philadelphia organization brought to Chicago by the team's new general manager, Dallas Green.

Harmon returned to his native Texas in 1983 as manager of the Double-A Midland Cubs and, after a period in private business, joined the Longhorns' coaching staff in 1989.^[4]