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.

Heffner was born in Allentown, Pennsylvania. He attended Allentown High School, now William Allen High School, where he graduated in 1957.

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

Throughout his Major League Baseball (MLB) career, Heffner was used both as starter and reliever. 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. Overall, he appeared in 114 games, 31 of which were as a starter.

• Career statistics from MLB, or ESPN, or Baseball Reference, or Fangraphs, or Baseball Reference (Minors), or Retrosheet
• Bob Heffner at SABR (Baseball BioProject)
• Bob Heffner at Baseball Almanac