Harmon died at Eisenhower Medical Center, hospital spokeswoman Lee Fowler said. She said she could not disclose the cause of death.
Harmon had been teaching at the Dick Harmon School of Golf at Redstone Country Club near Houston. Among his clients were Masters champions Fred Couples and Craig Stadler and former PGA champion Lanny Wadkins.
He had gone to visit one of his brothers, Bill Harmon, the teaching pro at Toscana Country Club.
'It's hard to believe,' Butch Harmon, the oldest brother, told Golfweek.com. 'It just came out of the blue. He was fine last night and gone this morning.'
The influence of the Harmon family is spread throughout golf. Butch Harmon, the oldest and most famous of the four, worked with Tiger Woods and Greg Norman when they rose to No. 1 in the world. Another brother, Craig, has been the pro at storied Oak Hill since 1972.
The four brothers reunited in Palm Desert late last month, working a three-day golf school together before flying on a private jet to Orlando, Fla., where their father was inducted into a teaching Hall of Fame. Claude Harmon won the Masters in 1948.
Dick Harmon had a golf show on a Houston radio station that he did by phone Thursday from Palm Desert.
He was the teaching pro at River Oaks Country Club for 24 years, retiring five years ago. Among his numerous awards were Southern Texas PGA Teacher of the Year, and he was recognized as one of the top 50 golf teachers by Golf Digest and Golf magazine.
'I didn't think there was a better short-game teacher than Dick,' Wadkins told Golfweek.
The hospital referred all questions to Bill Harmon, who did not immediately return a phone message.
Along with his three brothers and two sisters, Harmon is survived by his wife, Nancy, and four children.
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