Aljazeera's correspondent in Palestine reported that 17-year-old Husam Nasir was in his house when an Israeli bullet hit him late on Saturday night.
Witnesses said the bullet was fired by an automatic weapon from an Israeli armoured vehicle.
But an Israeli military spokesman said the army was not responsible for the killing.
"Our forces came under fire in the area, but they didn't shoot back because they could not identify the source," the spokesman said.
The latest death brought to 4190 the number of people killed since the start of Al Aqsa Intifada in September 2000, including 3193 Palestinians and 926 Israelis.