The 16-year-old boy walked into Fairfield Police Station around 11pm on Friday night with multiple stab wounds.
He was taken to Liverpool Hospital in a stable condition.
Teenager stabbed outside KFC in Fairfield. (9 News)
Police went to KFC in Fairfield where they found four teenagers in a parked car who were later arrested.
The boys, aged between 16 and 21, have been taken to the police station and are “assisting with investigations”.
Officers set up a crime scene in the KFC parking lot that is being investigated.
A 17-year-old boy was charged with wounding with intent to cause grievous bodily harm, affray and breach of bail.
He has been refused bail and will appear in court today.
The other three teenagers have been released.