Times must be tough at the North Pole, with a man dressed as Santa robbing a Melbourne post office.

Father Christmas walked into the Snell Grove post office at 11.30am on Saturday demanding cash.

A staff member handed over some money, which Mr Claus put in his red sack before leaving.

Rather than a reindeer-led sleigh, Santa escaped in a cream-coloured Jeep Compass with what police say were false plates.

Detectives from the Moreland Crime Investigation Unit say no weapon was sighted during the robbery.