The pilgrims were traveling back to Mumbai after visiting Hindu shrines in India's holy city of Nasik. The bus had a maximum capacity of 45 passengers but was carrying around 75.
The driver, who had been behind the wheel for three or four days, lost control of the bus on a sharp bend. He reportedly jumped out of the vehicle just before it crashed and is currently being questioned by police.
Local NDTV television cited the passengers and the driver as saying that the accident might have occurred because of brake failure.
Residents from nearby villages rushed to the scene to help using sheets to ferry the injured to hospital.
Pilgrims are often the victims of accidents in India. On August 9, at least 85 pilgrims died in a road crash in India's north-western state of Rajasthan when the truck they were riding in fell into a gorge. The pilgrims had been traveling to the shrine of a medieval Sufi saint.