A vehicle underfloor structure has: a battery pack that is disposed beneath a floor of a vehicle, and that is a power source that drives a motor for traveling that is installed in the vehicle; and a fuel tank that is disposed beneath the floor of the vehicle, and between a vehicle body front side end portion and a vehicle body rear side end portion of the battery pack as seen in a side view, and between vehicle transverse direction both end portions of the battery pack as seen in a plan view.