Joshua Malmgren, 30, of Lower Township, N.J., was arrested at the scene.
The accident happened around 9:20 p.m. Tuesday on Bayshore Road near the Green Creek Fire House in Middle Township.
The Cape May County prosecutor's office said an SUV struck the teens as they were walking along the shoulder.
Two cousins, Ashley Dauber, 13, and Naomi Lazicki Gaston, 15, were pronounced dead at the scene.
A 14-year-old girl, a sister of one of the victims, was also walking with victims but was not hurt.
Malmgren was charged with two counts of second-degree death by vehicular homicide, driving while intoxicated, reckless driving, failure to maintain a lane of travel and consumption of alcoholic beverage by an operator of a motor vehicle.
Malmgren was committed to the Cape May County Correctional Center in lieu of $50,000 cash bail.
The prosecutor said anyone convicted of a second-degree crime faces five to ten years in state prison.