The man, who had been working at the Hospital Inn, was in the Hospital Inn pub car park with a female colleague when they were approached by a group of men at around Midnight on May 30.
Investigating officers say that the men then assaulted the pair before stealing the woman's purse which contained Â£100.
A spokesman for Lancashire Police said: "We were called at around 11.55pm on Monday, May 29 following reports of a robbery in Brindle Road, Bamber Bridge.
"A man and a woman were approached by a group of men close to The Hospital Inn. The group assaulted the pair causing minor injuries before taking the woman’s purse. containing Â£100.
"The offenders then made off from the scene."
Ambulance services attended the scene and took a man to Royal Preston Hospital with cuts to the head and a busted lip. The woman was treated for minor injuries at the scene.
Manager of the Hospital Inn Lynn McIndoe said: "I can confirm there was a robbery last night involving two members of staff from the Hospital Inn. The incident involved two members of staff.
"One person was taken to hospital and both staff members were left badly shaken.
"We take the safety of our staff very seriously and we are obviously concerned for the welfare of the two people affected.
"We wish them a very speedy recovery. We are now assisting the police with their on-going enquiries."
A police dog handler was shot in the leg when four masked men raided the Hospital Inn in 2007.
Anyone with information can contact police on 101 quoting crime reference SA1702113.