A rear vehicle-body structure of a vehicle can enhance the performance of protecting a vehicle component disposed under a rear floor against a rear-end collision load. The rear vehicle-body structure of a vehicle includes a rear bumper reinforcement having a rear bumper beam extending in a vehicle width direction along a rear bumper and load absorbing parts extending from left and right ends of the rear bumper beam toward a vehicle front side, and rear side frames extending in a vehicle front-rear direction respectively along left and right side portions of a rear floor and coupled at rear ends to front ends of the load absorbing parts, with a vehicle component being disposed under the rear floor. A vertical center of the rear bumper beam is located lower than a respective vertical center of each of the rear side frames.