The force was called to the Adelphi Hotel in the early hours of Saturday.
They were alerted around 6.37am following reports of concerns for the safety of a woman.
Police later found the body of a 22-year-old woman in a downtown hotel.
A 26-year-old man, a 46-year-old man and another 49-year-old suspect have been arrested on suspicion of murder in connection with the incident, Liverpool ECHO reported.
The outlet added that Merseyside Police remained “open” to all avenues of investigation.
Detective Chief Inspector Lynsay Armbruster said: ‘We are in the early stages of our investigation and are working to establish the circumstances surrounding the death of this young woman.
“I would ask anyone in the hotel early this morning to come forward if they saw or heard anything.
“The CCTV investigation is ongoing and I would call on anyone with information to get in touch.”