Police are now appealing for any witnesses or information.
At around 5.30pm on Monday 6 April the guard was removing cash from an ATM on Bolton Road when two men ran at him waving an axe.
In his terror he dropped a cash box which was picked up by the two thieves who fled the scene on foot, and were last seen running across the A580 East Lancs Road heading towards the Duchy estate.
The cash box and all of its contents were later recovered on Summerville Road.
The first man is described as being around 5ft 10in tall and of slim build. He was wearing a grey top and carrying an axe.
The second man was wearing a blue tracksuit.
Detective Constable Andrew Quinn of Salford division said: “This was a violent robbery and a terrifying ordeal for the victim.
“Thankfully he wasn’t injured but nobody should be threatened with an axe when they are just doing their job.
“I would urge anyone with information about the incident to contact police immediately.”
Anyone with information should phone police on 0161 856 2282 or the independent charity Crimestoppers, anonymously, on 0800 555 111.
