The assault happened at about 1.50am yesterday (Sunday), outside The Waterhouse pub in St Thomas Street.
Police said a 36-year-old man was hurt following an altercation involving a group of men and women.
The victim, from Middlesbrough, was taken to hospital after suffering fractures to his jaw, cheek bone, eye socket and nose.
Two men, 37 and 30, and a 27-year-old woman, all from Scarborough, were arrested in connection with the incident.
They have now been released under investigation while enquiries continue, police added.
Anyone with information is asked to call North Yorkshire Police on 101, quoting reference number 12180215460.