To provide the rear body structure of a bus excellent in a vehicular weight distribution and a production workability which can restrain a vibration and the noise on a room end improve a comfortable ride.

This rear part structure has a support member 30 for supporting a power unit constructed between a rear end frame 29 and front end frame 23, a rear pillar 24 joined to both ends of the front end frame 29, a rear end pillar 25 joined to the rear end frame 29, sub-frames 27a, 27b... constructed between the rear pillar 24 and the rear end pillar 25 and a vertical support member 33 for connecting the center part of the rear end frame 29 to a rear member 35. The front end frame 23 and the rear end frame 29 are integrally formed by the support member 30, rear pillar 24, rear end pillar 25, sub-frames 27a, 27b..., rear member 35 and vertical support member 33 and the load of the power unit is dispersed and supported to the front end frame 23 and rear end frame 29 improved their rigidity and the vibration and noise caused by the power unit is reduced and a comfortable ride is improved.