Born in Tampa, Florida he was educated at Bolles School, Jacksonville and the University of Florida. He joined the USAF in March, 1950 after completing his aviation cadet training. He was assigned to the 86th Fighter bomber Wing based at Ramstein AFB in West Germany. In 1954 he was transferred to Holloman AFB in New Mexico and the Air Force Missile Development Center (AFMDC). In 1957 as part of Man High he set a balloon altitude record of 96,000 feet in Man High I. He was awarded the Distinguished Flying Cross.
He was then assigned to the Aerospace Medical Research Laboratories at Wright-Patterson AFB in Dayton, Ohio. For Project Excelsior, as part of research into high altitude bailout, he made a series of high altitude parachute jumps, from 76,400 feet (23,287 metres) in November, 1958; from 74,700 feet (22,769 metres) in December, 1958. On August 16, 1960 he jumped from the Excelsior III at 102,800 feet (31,333 metres). He was in freefall for 4½ minutes and reached a maximum speed of 614 mph (982 km/hr) before opening his parachute at 18,000 feet (5,486 metres). He set records for highest balloon ascent, highest parachute jump, longest freefall and fastest speed by a man through the atmosphere. For his jumps he was decorated with an oak leaf cluster to his D.F.C. and awarded the C.B. Harmon Trophy.
Back at Holloman AFB he also took part in Project Stargazer on December 13-14, 1962. He and William C. White, an astronomer, took a balloon of equipment to a height of 82,200 feet (25,055 metres) and spent over eighteen hours at that height in performing observations.
Kittinger served three combat tours during the Vietnam War, commanding the 555th Tactical Fighter Squadron. He was shot down on May 11, 1972 and spent almost a year as as prisoner of war.
He retired in 1978 and went to work for Martin Marietta. Still interested in ballooning he won the Gordon-Bennett balloon race three times (1982, 1984, 1985) and completed a solo Atlantic crossing in the 3,000 m³ Rosie O'Grady from September 14-18, 1984.