A polygonal cross-sectional frame has an L closed cross-sectional shape such that the frame has an inwardly recessed section. A rear vehicle body structure includes a depressing member provided, along the lower surface of a rear frame extending rearward from a floor of a passenger compartment, in opposed relation to a predetermined vehicle-body-mounted component part disposed beneath the depressing member. As a rear section of the rear frame deforms due to a load input to the rear end of the rear frame, the depressing member deforms downward to depress and displace the predetermined vehicle-body-mounted component part.