A video shows two groups of men fighting each other in Newquay.
In the clip, filmed by holiday makers in Cornwall, shows a group of men, believed to be on Barton's stag do, brawling with another group.
One man dressed all in black knocks three different people to the ground after punching them in the face.
The Fleetwood boss is to marry his fience Georgia McNeil in the summer.
A spokesman for Barton said:
"Joey categorically denies being involved."
Police in the area say no incident has been reported.