The cause of death has not yet been disclosed.
Bundy posted on Twitter just four hours before his death, promoting a meet-and-greet session with fellow wrestler Al Snow in April.
Bundy was born in Atlantic City, New Jersey and the 1.93m, 208kg wrestler made his World Wrestling Federation debut in 1981.
He was best known for facing Hulk Hogan in 1986 in a steel cage match at WrestleMania 2, which Hogan won.
He was a regular in the WWF in the 80s and 90s, going up against big names like the Undertaker and Andre the Giant.
Hogan said he was "overwhelmed" by his friend's passing.
The WWE paid tribute to Bundy's contribution to wrestling with a statement on the organisation's website.
"WWE is saddened to learn that WWE Legend King Kong Bundy has passed away," the statement read.
During his career, Bundy also made guest appearances on the US television sitcom Married … with Children.
He was planning to appear at the WrestleCon event in New York City next month.