Rescue workers said that the bus, which plunged off of a paved highway roughly 60km northwest of Guatemala City, was completely destroyed and that 46 people had been taken to nearby hospitals to be treated for injuries.
Investigators do not yet know what caused the crash or what was the final destination of the bus, which was traveling south toward Guatemala City. Rescue workers said that conditions were dry and mostly sunny and that the bus was likely over capacity.
"There are 38 dead, among them six children and 12 women," said Sergio Vasquez, a volunteer firefighter at the site of the accident.
Local television said many of those on the bus were vendors taking farm produce to market.
The last major bus accident in Guatemala occurred in 2008 when an overcrowded bus slid off a highway and down a 15m slope some 65km southeast of the capital, killing 53.
