The former Tonight Show sidekick passed away in the early hours of Tuesday morning at the Ronald Reagan UCLA Medical Center in Los Angeles.
The veteran star had been battling ill health for some time. He was diagnosed with systemic bone cancer and spent time in the hospital in February, suffering from pneumonia.
McMahon began his career as a fighter pilot during World War II, serving in Korea throughout the 1950s.
He went on to work with legendary star Carson on daytime game show Who Do You Trust?, and in 1962 the pair landed the job of hosting The Tonight Show.
McMahon spent more than 30 years working alongside Carson on the popular entertainment program. He went on to host hit 1980s talent show Star Search, and his other TV projects included hosting NBC series TV Bloopers and Practical Jokes alongside Dick Clark.
McMahon's final years were plagued by legal troubles and financial difficulties. He struggled with a neck condition caused by a 2007 fall at a friend's house and subsequently sued the homeowners and doctors at an L.A. hospital, who he claimed misdiagnosed his neck fracture.
His recent legal woes included various lawsuits relating to mold at his California mansion and financial difficulties, which saw him come close to losing his home after falling behind on mortgage payments.
The cause of McMahon's death was not confirmed as WENN went to press. He is survived by his wife Pam Hurn and five children.
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