An off-road vehicle has a frame, at least four wheels, a seat, a steering assembly, an engine, and a cargo box pivotally mounted to the frame rearwardly of the seat. The cargo box includes: a cargo box body having a front wall, a pair of side walls, a lower floor, and an opened rear side; an upper floor supported inside the cargo box body above the lower floor; an upper tailgate for selectively closing an upper opened portion of the opened rear side; a lower cargo space defined at least in part between the front wall, the pair of side walls, the lower floor, and the upper floor; and an upper cargo space defined between the front wall, the pair of side walls, the upper floor, and the upper tailgate when the upper tailgate closes the upper opened portion of the opened rear side.