27-year-old Ossie Thomas of Mount Laurel was charged following the January 8 crash in Willingboro.
Thomas is also accused of driving while intoxicated and driving with a suspended license.
Investigators say Thomas was speeding on Rancocas Road and lost control while attempting to turn onto Primrose Lane.
The car crashed into a wooded area.
One of the twins was taken to the hospital but was pronounced dead about an hour later.
The other twin was hospitalized and treated for a traumatic brain injury. The child has since been released.