Police have found a large amount of fake $50 notes in circulation at a shopping centre in south-east Melbourne.

About $1,000 worth of counterfeit notes was spent at Chadstone shopping centre yesterday.

Officers are looking for two men, believed to be of Middle Eastern appearance, who are accused of using the fake money.

The notes can be identified as bogus because the clear window appears to be glued on and they are much easier to tear.

They also have a much larger depiction of the Southern Cross compared to legitimate cash and do not have an embossed "50" in the clear window.

Victoria Police are asking shop owners to put the fake notes in an envelope and hand them in to police.

Officers are also appealing for people to come forward with descriptions of the people who used the notes and any vehicles they may have travelled in.