inwardly in the vehicle width direction from the rear end portion 66 a toward the front end portion 66 b the present invention is not so limited for example the left and right longitudinal protruding sections 66 and 67 may be widened only outwardly in the vehicle width direction from the rear end portion 66 a toward the front end portion 66 b even in the case where the left and right longitudinal protruding sections 66 and 67 are widened only outwardly in the vehicle width direction the same advantageous benefits as in the above described embodiment can be achieved the shapes and constructions of the subframe left and right suspension arms left and right suspensions body section left and right suspension support sections upper section lower section transverse protruding section left longitudinal protruding section right longitudinal protruding section recessed section left and right front connection sections left and right rear connection sections core etc are not limited to those illustratively shown and described in relation to the embodiment and may be modified as appropriate the basic principles of the present invention are well suited for application to automobiles equipped with a subframe which is provided under a vehicle body and in which left and right suspensions are supported by left and right suspension arms connected to a subframe body 10 front vehicle body structure 15.