At the inner side adhesion portion 28, a portion of the inner side vertical wall portion 22 is formed so as to be recessed to an inner side. An inclination angle θ2 of the inner side adhesion portion 28 with respect to a vehicle up-and-down direction is set to be greater than an inclination angle θ1 of the inner side vertical wall portion 22. At the outer side adhesion portion 38, a portion of the outer side vertical wall portion 32 is formed so as to be recessed to the inner side. An inclination angle θ4 of the outer side adhesion portion 38 with respect to the vehicle up-and-down direction is set to be greater than an inclination angle θ3 of the outer side vertical wall portion 32.