Samaranch died at a hospital in his native Barcelona, Spain, of apparent heart failure, officials said.
"I cannot find the words to express the distress of the Olympic family," IOC President Jacques Rogge said in a release. "I am deeply saddened by the death of the man who built up the Olympic Games of the modern era; a man who inspired me and whose knowledge of sport was truly exceptional.
"Thanks to his extraordinary vision and talent, Samaranch was the architect of a strong and unified Olympic Movement."
Samaranch, a Spanish diplomat and a long-time official with the country's Olympic team, was elected to the leadership position of the IOC in July 1980 and held the post until July 2001. Under his leadership the IOC negotiated lucrative broadcast and sponsorship contracts that made the Games financially viable.
He also pushed for the Olympics to make sure all of the best athletes were eligible to compete in the Olympics, a move that shifted the Games from an all-amateur format to the acceptance of professional athletes.