The incident happened just after 1:00am on Sunday 15th July outside the town hall on Blackburn Road.
The man suffered a broken cheekbone and jaw and has had to have metal plates and pins fitted as a result of this attack.
PC Jo Galeski said, “This is a serious and unprovoked attack on an innocent member of the public and the person responsible needs to be caught and brought to justice.
“The victim required medical treatment and has been left shaken following this attack and is now recovering at home.”
Anyone with information is asked to call Accrington police on 101.