National Park Service rangers say they responded to an emergency call about 3 a.m. Sunday. Witnesses say the man had been fishing in the Temple Bar Marina area when his lure snagged on some vegetation.
He was unable to loosen it and went into the water to try to free the lure. Witnesses say they heard calls for help and splashing, then silence.
Rangers recovered the man's body in about 6 feet of water Sunday morning.
The Mohave County Coroner's Office has identified him as Roderick Rayford.
Officials are investigating the death.