Labor's plan to lift a ban on controversial cage fighting if it wins the election has been dealt a blow with Victoria's top police officer arguing against the sport.

The Herald Sun has reported Chief Commissioner Ken Lay warning that lifting the ban on cage fighting would lead to more violence in the state.

Ultimate Fighting Championship would hold an event at Etihad Stadium if Victoria's cage fighting ban was lifted. Credit:Chris Lane

In 2008 the then-Labor government banned cage fighting. The sport of mixed martial arts is not illegal but conducting it within a caged area is.

"It concerns me when we start considering cage fighting in the world's most liveable city, especially when we're seeing such great progress in reducing violence in our community," Mr Lay said.