According to the newspaper La Nuova Venezia, a group of four tourists climbed aboard a stationary gondola to take pictures near the Bareteri bridge, in the heart of the historic centre.
The gondolier reportedly asked them to disembark and a standoff ensued, during which the local boatman got swiped at and headbutted.
A video filmed by onlookers and shared on Facebook shows a man jostling and threatening a gondolier, knocking off his traditional straw hat before headbutting him and hitting his face.
In the video, the gondolier argues with the man but does not hit him back.
This is not the first time an incident such as this has happened with tourists, according to the newspaper, since the popular city has been waging a battle with overtourism.
The relationship between Venice and its visitors is often strained, with the city’s economy dependent on tourism but its residents increasingly frustrated with the crowding and disruption that comes of hosting 12 million tourists per year.