The incident took place when the bus crashed into a truck leaving 19 dead and wounded, according to police.
All of the injured passengers were transported to the nearby hospital and their health conditions are critical.
Local media reported that the bus was traveling at high speed when it hit the back of the truck on a highway in the western district of Subang.
Initial reports said the driver of the bus might have been drowsy. Police are still investigating the case.
Road accidents in Indonesia are frequent and usually spike up during holidays.