The victim was waiting for the number 5 in Strensall, near York, at 9pm last Friday when the attack took place.
Police said the local man had been standing at the stop near the Londis petrol station on Strensall Road when he was approached by three men from a group of nine.
A spokesman said: "He was punched in the face and hit over the head with a glass bottle.
"The attack left the man with a broken jaw, which has since required surgery, and deep lacerations to his mouth."
Officers want to speak to anyone with information as well as anyone who was in the area of Strensall Road at the time of the attack.
Call 101, select option 2 and ask to speak to the York Serious Crime Team, quoting reference 12170202607.
Alternatively, Crimestoppers can be contacted anonymously on 0800 555 111.