They say a woman spotted the boy staggering alongside Jackie Robinson Parkway near Cypress Avenue in Queens and called 911.
Reports say the boy was stabbed a dozen times in the back. He was rushed to Jamaica Hospital in critical condition.
Authorities believe the boy was smoking pot with a 15-year-old friend when they got into a fight. The 15-year-old allegedly slashed him several times across the face.
The 15-year-old is under arrest. His name is not being released because he's a minor.