The truck, which was carrying 13 people, veered off a steep mountain road in Yilong county of Nanchong City at about 4.20 a.m., Xinhua reported citing traffic police.
Six people were killed at the scene and another succumbed while being taken to hospital.
The five injured passengers were being treated in the People’s Hospital of Yilong county.
According to traffic police, four of them were slightly wounded but one was in critical condition.
The truck driver was the only one who survived without injuries.
The driver told police that it was raining and his vehicle had broken down on the slippery mountain road.
Shortly after he got out of the truck to check the road condition, the vehicle suddenly slid backwards and fell off the cliffside.