The incident occurred at Shyam Colony, Ballabhgarh in Haryana's Faridabad district, which is less than 50 kilometers away from Delhi.
The teenager was rushed to hospital with two bullet injuries.
Police are looking for the accused.
The girl was shot outside a private library where both the 17-year-old and the shooter regularly visit for study sessions.
After shooting the girl, the man threw his weapon on the spot from where police recovered a homemade pistol.
As per reports, the girl could identify the shooter and told police that she was previously harassed by the same person.
The entire incident was caught on CCTV. The shooter was standing beside a motorcycle and waiting for the girl.
When the girl arrived, he fired on his shoulder and abdomen and then fled on the bike.
The two girls who were accompanying the victim initially drifted away during the shooting out of panic, later rushed to her help when the accused fled the spot.