To provide a vehicle body structure for an autonomous traveling vehicle equipped with wheels arranged to a chassis thereof, including; side frames arranged on both sides in a width direction of the chassis and each extended in a longitudinal direction of the chassis; a first drive unit having a drive motor, a drive shaft, a first pulley and a first pulley box; a second drive unit having an axle for supporting the wheel and a second pulley and a second pulley box; and an endless belt. The first pulley box has a first opening formed on a side surface, with respect to an axial direction of the drive shaft while the second pulley box has a second opening formed on a side surface with respect to an axial direction of the axle. The vehicle body structure includes bearing covers for covering the first and second openings.