Between 1.30am and 1.45am on Sunday (6/10) the victim, a 24-year-old man, was on the dance floor inside Fever & Cirque night club in Kingsbury Square when he was assaulted.
He was left with a fractured cheekbone.
The offender hit his victim several times and he fell to the floor. The victim has no recollection of the incident.
Investigating officer Detective Constable Hannah Davison of Force CID based at Aylesbury police station, said: “This was an apparently unprovoked attack which has caused significant injuries to the victim.
“We have viewed CCTV and there were many people still in the club and I believe that there will have been witnesses to what happened.
“We have a very limited description of the offender, only that he was a white man.
“The victim suffered a fracture to his cheek bone and remains in the John Radcliffe Hospital in Oxford.
“I am appealing to anybody who was in the night club in the early hours of Sunday morning and who believes that they witnessed this incident, or knows who the offender is, to call the 24-hour non-emergency number 101, quoting reference 43190309072.
“If you do not wish to speak directly with police, you can make a report online or call the independent charity Crimestoppers anonymously on 0800 555 111.”