Robert Frederic Heffner (born September 13, 1938), nicknamed "Butch", is a retired Major League Baseball right-handed pitcher with the Boston Red Sox (1963–1965), Cleveland Indians (1966), and California Angels (1968).

He stood 6 feet 4 inches (1.93 m) tall and weighed 200 pounds (91 kg), in his playing days.

On June 12, 1957, Heffner was signed by the Boston Red Sox as an amateur free agent right out of high school.

His most productive season came in 1964 with the Red Sox, when he posted career-highs in wins (seven, including a shutout), strikeouts (112), saves (six), games (55), and innings (158+2⁄3).

Hefner's five-season MLB career totals include an 11–21 W–L record, a 4.51 ERA, and six saves.