The passenger was identified as Gerardo Nales, 42, of Key Biscayne, ABC News reported. The identity of the pilot and the owner of the plane have not been released.
Police said the pilot was cooperating with investigators.
A search began Thursday afternoon, shortly after the pilot called in a Mayday message and returned to Kendall-Tamiami Executive Airport. It was halted late Thursday and resumed Friday.
The pilot told air traffic controllers the passenger, the only other person on board, had opened a door and fallen out.
Earlier this month, a man chartered a helicopter in Newport Beach, Calif., and jumped from it, in what has been deemed a suicide.
Miami-Dade Police spokesman John Jenkins Jr. told The Miami Herald late Thursday the search was being treated as a recovery operation.
"It's safe to say someone falling out of an airplane without a parachute is going to be deceased," Jenkins said.
The pilot sent a Mayday message to air traffic controllers at about 1:30 p.m.
"Mayday! Mayday! Mayday! I have a door ajar and I'm heading toward Tamiami," he said, speaking calmly. "I have a door ajar and a passenger that fell down."