At about 8.20pm on Saturday, July 5, emergency services were called to the party on Carnegie Court in Chifley.
Police were told a 16-year-old boy and an 18-year-old man were out the front of the house when they were approached by a group of about 10 people, two of whom were allegedly armed with machetes.
The 16-year-old boy was allegedly attacked and stabbed by members of the group before they left the scene.
The teen was treated for lacerations to his back and legs before he was taken to hospital in a stable condition.
Yesterday, police arrested a 16-year-old boy and charged with multiple offences, including reckless wounding, drug possession, and weapon possession.
He was refused bail and will appear in court today.
The investigation continues.
Anybody with information, dashcam, or mobile phone footage is urged to contact Maroubra Police Station, or Crime Stoppers on 1800 333 000.
