The incident occurred when the bus, on its way from Barthin(Bilaspur) to Bhota (Hamirpur) skid off the road, an official spokesman said.
The passengers said rash driving was the cause of the accident.
While the injured were immediately taken to Bhota hospital, eight others who were seriously injured were rushed to zonal hospital Hamirpur for treatment, the officer said.
A case has been registered against the driver by Hamirpur police, he said, adding, SDM, Badsar, announced a relief amount of Rs 5,000 for the eight who are seriously injured.