The 15 year-old was assaulted by up to five teenagers on Chapel Road, Londonderry, during the early hours of Sunday.
The victim was walking with a friend when he was approached by the teenagers.
One member of the group punched him in the face causing him to fall to the ground where he was kicked a number of times.
He sustained bruising to the face and back in the attack.
Police have not confirmed whether the assault was sectarian. A spokesperson said: "A motive for the attack is still under investigation."
Witnesses to the attack which took place at around 1.30am on Sunday have been urged to contact police on 0845 600 8000 or Crimestoppers on freephone 0800 555 111.