The tragic accident happened in the Ramnagar district and the car's driver was also killed in the crash.
Pooja Mauria, 30, her husband Himanshu Aswal, 32, and his mother Saroj Bala, 58, were killed in the accident besides the driver of the car Surat Saini, a police official told news agency PTI.
The family was travelling from Dehradun to Haldwani when the incident occurred. The accident took place 12 Km from Ramnagar near Haldwa Village on the national highway.
(With PTI inputs)