Robbers used a Transit van to smash their way through the front of a post office before fleeing with the cash machine.
The ram-raiders tore through the shutters and glass front of the building in Parkgate, Chadderton, before leaving the vehicle outside. They made off in a silver Volkswagen Touran and a blue or black Vauxhall Astra.
Officers were called to the smashed up shop at 11.50pm yesterday.
An investigation is underway and officers are urging anyone with information to come forward.
Detective Constable Rich Whiting of Oldham CID said: "These offenders caused massive damage to the building and it will take some time for the Post Office to get back up and running again.
"We believe there may have been witnesses who were in a car nearby at the time of the burglary, but we were not able to speak to them as they had left before we had arrived.
"If you witnessed what happened, please contact us as your information could be vital to us finding the people responsible.
"There were a number of vehicles involved in this so I want to hear from anyone who saw anything suspicious in the lead up to this burglary, or if you simply have information of who has committed this crime, please don't hesitate to get in touch."
Witnesses should call police on 0161 872 5050 or Crimestoppers, anonymously, on 0800 555111.
