A front underfloor structure of a vehicle includes front deflectors disposed forward of front tires, respectively. The front deflectors each include a front apex portion disposed at a position closer to the vehicle front than a leading edge surface of each of the front tires when straight, and disposed at a position closer to a vehicle center line than an inner surface of each of the front tires when straight; an outer end portion disposed at a position closer to the vehicle rear than the front apex portion, and disposed at a position outward in the vehicle width direction of the front apex portion; and a second flow redirection surface connecting the front apex portion and the outer end portion, and being configured such that, when struck by air traveling from the vehicle front, the second flow redirection surface redirects a flow of the traveling air outward in the vehicle.