Emergency services were called about 12.05pm yesterday following reports an 18-year-old woman had been stabbed in the head with a spear by a man known to her in Angurugu, a community on Groote Eylandt in the Gulf of Carpentaria.
The woman was found unconscious at the scene with the weapon still embedded in her head.
She was then taken to Royal Darwin Hospital via Care Flight in a serious but stable condition.
No arrests have been made and police are now searching for the alleged offender.
Anyone with information is urged to contact police or Crime Stoppers on 1800 333 000.
For 24/7 crisis support run by Aboriginal and Torres Strait Islander people, contact 13YARN (13 92 76).