Officers were called to a house in Ashton View, Harehills, yesterday evening and found the man with a serious head injury.
He was taken to hospital for treatment but was pronounced dead a short time later.
Detectives are understood to be in the early stages of establishing what happened and it is not currently being treated as a murder investigation.
A 35-year-old man and a 24-year-old woman who were yesterday arrested in connection with the incident are still being held in custody.
Anyone with any information is asked to contact the police via 101 quoting log number 1379 of December 6.