REAR VEHICLE BODY STRUCTURE

This rear vehicle body structure includes a first floor cross member disposed on a vehicle front side with respect to a battery and connected to a rear side frame extending in a vehicle front-rear direction on an outer side in a vehicle width direction, and a second floor cross member disposed on a vehicle rear side with respect to the battery, in which the first floor cross member includes a widened part widened in the vehicle front-rear direction at an end portion and extending to a position at which it overlaps the battery, and a boundary part between the widened part and the rear side frame is disposed at a position at which it overlaps the battery in a side view.