This lower vehicle body structure includes a pair of side frames extending substantially in a vehicle body front-rear direction at a rear side or a front side of a center in the vehicle body front-rear direction, a cross member connected to the pair of side frames, and a floor panel structure joined to the pair of side frames and the cross member, in which the cross member includes a pair of inclined extension portions bent at an obtuse angle and extending from both end parts of a central region in a vehicle width direction toward a center side in the vehicle body front-rear direction, the floor panel structure includes a reinforcing bead extending from a position on an outer side of the cross member in the vehicle body front-rear direction toward the center side in the vehicle body front-rear direction to be in contact with the cross member, and the reinforcing bead extends to a position that does not reach a joint portion of the cross member with the floor panel structure on the center side in the vehicle body front-rear direction.