The harrowing scene took place on Royal Caribbean’s Oasis Of The Seas, one of the largest cruise ships in the world.
It left Florida on Saturday and was 70 miles east of the Caribbean islands of Turks and Caicos when the 35-year-old man plummeted into the ocean.
A passenger on the boat tweeted: “There was a struggle. Security tried to save him. It looks like he jumped.”
Another passenger told INSIDE EDITION: "We circled all night long. At daybreak they launched a plane, I think it came out of Florida. Then we returned to Fort Lauderdale.”
The Coast Guard continues to search for the man.
In a statement, Royal Caribbean said: "Our care team is providing support to the guest's family and our thoughts and prayers are with them during this difficult time.”
This is not the first time the Oasis of the Seas has experienced drama.
In January 2014, off the coast of Mexico, a 22-year-old from Colorado somehow went overboard and because no one saw him fall into the sea, the ship steamed away.
Incredibly, he managed to stay afloat until a Disney cruise ship came by and rescued him.