His wife, Kathe, said he had been diagnosed with leukemia Tuesday, the day before he died, the Baltimore Sun reported.
Dobson, who joined Jim Palmer, Dave McNally and Mike Cuellar in the historic 1971 rotation, was remembered by former colleague Palmer as "a free spirit. He could laugh at himself. Dobson really enjoyed life."
"He was a real gamer, a real competitor," Hall of Fame outfielder Frank Robinson said.
Dobson, who worked for the San Francisco Giants the past nine years, was 122-129 with a 3.54 ERA in 11 major league seasons. He won a World Series ring with the Detroit Tigers in 1968.
Dobson, who lived in El Cajon, Calif., is survived by his wife, three children from his first marriage, two step-children and a grandchild.