Leicestershire Police said officers were called by East Midlands Ambulance Service, who were treating an injured man, at 4.23am on Friday.
He was taken to the hospital with a serious head injury and has since died, according to the police.
A 20-year-old man who had been detained at the scene on suspicion of assault has been released on bail, while detectives continue their investigation.
Anyone who witnessed the attack or the events leading up to it is asked to call 101.
You can also provide information anonymously to the independent charity Crimestoppers by visiting their website at www.crimestoppers-uk.org or calling their UK Contact Centre at 0800 555 111.
