Hussain Meer, 26, Mir Wayne Carew, 25, Yanne Sarkawt, 25, and Malique Kai Walters, 27, allegedly threatened the tourist with a knife and a gun before snatching the watch, Metro reported.
Video footage shows four assailants knocking the man to the ground and pulling the watch from his wrist.
The victim told police he has visited Thailand more than 60 times and had been in the country for 10 days when the robbery occurred, Khaosod English newspaper reported.
The Britons had arrived in Thailand as tourists.
Police said they have traced the suspects' movements, located all vehicles used in the crime, and collected additional evidence.
The men have been charged with jointly committing robbery.
The watch was recovered and returned to its owner, prompting the victim to praise Phuket police for their professional and efficient work.