The crash happened Tuesday on the A 12 highway in the state of Brandenburg between the towns of Storkow and Fredersdorf.
Police said 35 people were hurt, including six with severe injuries, dpa said. Three helicopters, ambulances and police officers were on the scene, and the section of highway was closed.
Police said the truck, which was traveling in the direction of Berlin, collided with the side of the bus when it tried to change lanes.