Emergency Services attended the scene close to the library at Harbour View Road in Knocknaheeny at around 11:45 last night.
The girl, who was a passenger in the car, was pronounced dead at the scene.
The driver and a second passenger, both males in their teens were seriously injured in the collision and rushed to CUH where the second passenger's condition is believed to be critical.
Harbour View Road remains partially closed to facilitate a technical examination and diversions are in place.
Gardaí in Gurranabraher are appealing for witnesses or anyone with dash cam footage of the area to contact them on 021 494 62 00
