A man has been captured on CCTV stripping off his clothes and jumping on a police speed camera vehicle in Melbourne's south-east.

Police released the footage showing two men walking past the camera on Kelletts Road in Rowville around 1:30pm on Australia Day.

One of the men takes off his clothes, jumps on the front of the vehicle and begins howling abuse at the speed camera operator inside.

The ordeal goes on for about 30 seconds before the men continue walking along the road.

About an hour later the men, stocked up with alcohol, return to the vehicle.

The same man strips off again and performs a series of lewd acts on the car before leaving again.

Police are hopeful someone will be able to identify the men involved.