Officers today appealed for information about the people pictured after the offending on Sunday, February 25 on Duncan Street near to the Space nightclub.
PC Lee Armstrong, of Leeds CID, said: “This was a vicious assault and one which left the victim with a serious head injury.
“I would like to appeal to the public to come forward with any information about the incident itself or to help identify the people in the images we are releasing today to assist with our ongoing investigation.”
In its appeal West Yorkshire Police said the victim, an 18-year-old man, left Space Nightclub and made his way on to Duncan Street.
He left the club and had an "altercation" with another two men, who ran at him and punched him in the head, causing him to fall to the floor and hit his head on the ground.
Police said the victim suffered serious injuries and was taken to hospital for treatment.
The first suspect is described by police as an Asian man aged 25 to 35 with facial hair. He was wearing a distinctive long-sleeved top with a large skull on the front.
The second suspect is described as a white male, 6ft, of slight build, with short hair which was combed over to the side. He was wearing a blue T-shirt.
The men stood outside of the club with two women, one of whom was wearing a bright orange top.
Anyone with any information, who witnessed the assault or who recognises the people in the photos is asked to contact the police via 101, quoting crime reference number 13180093327.
Information can also be passed to Crimestoppers anonymously on 0800 555 111.