About 100 people were at a gathering on Murrays Beach in Sawtell, near Coffs Harbour on Sunday night when a fight broke out.
A 16-year-old boy was stabbed multiple times in the arm, stomach, and back before bystanders intervened.
He was treated at the scene by NSW Ambulance paramedics, before being taken to Coffs Harbour Health Campus for treatment, where he remains in a serious but stable condition.
A 17-year-old boy turned himself into Lismore Police Station, about 200km north of Sawtell, shortly before 11am today, police said.
This evening he was charged with with wound person with intent to cause grievous bodily harm and affray.
The teenager was refused bail to appear before a children’s court tomorrow.
Anyone with information about the incident, or who may have mobile phone footage, is asked to come forward.
