He died of respiratory failure in Los Angeles on Friday (04May12), according to the New York Times.
Born in Brooklyn, New York, Stewart served in the U.S. Air Force during World War II before taking up a career in broadcasting.
In 1956, the producer developed U.S. game shows The Price Is Right and To Tell the Truth, and he invented beloved word association TV programme Password five years later.
Stewart went on to form his own production team, Basada, Inc., and created $10,000 Pyramid, which eventually garnered nine Emmy Awards, primarily under the leadership of host Dick Clark.
Stewart retired from the business in 1991 and in 2010, he was inducted into the Academy of Television Arts & Sciences Hall of Fame by small screen legend Betty White.