At least 20 people were killed and one was injured in a road accident on Thursday in western department of La Paz, police said.
A truck with 25 people onboard plunged into a 250-meter-deep ravine when it was traveling on a mountain road, Xinhua reported.
A 9-year-old girl survived as she dropped out of the falling truck and was miraculously trapped in the bush.
A police officer said until 20:00 local time (0000 GMT Friday) only 18 bodies had been recovered as the site was very steep.
It was likely that the driver fell asleep, which caused the truck to plunged off a cliff with a depth of up to 300 meters in some places, police said.
Road accidents are common in Bolivia, South America's poorest country, where driving conditions are often precarious.