A vehicle electric motor (10; 210; 310; 410) comprising: a tubular-shaped stator core constituted by a plurality of steel sheets that are laminated on each other; a casing including an outer circumferential wall and a bottom wall, and storing therein one of opposite end portions of said stator core which are opposite to each other in an axial direction of said stator core; a casing cover including an outer circumferential wall and a bottom wall, and storing therein the other of said opposite end portions of said stator core, said casing cover being fixed to said casing; and a rotor disposed inside said stator core so as to be rotated about an axis of said stator core, wherein said stator core includes a plurality of fastened portions (34a, 34b, 34c) provided in respective portions of an outer circumferential surface of said stator core which are spaced apart from each other in a circumferential direction of said stator core, said fastened portions (34a, 34b, 34c) protruding outwardly in a radial direction of said stator core, said stator core being fastened at said fastened portions (34a, 34b, 34c) to said bottom wall of one of said casing and said casing cover, through fastening bolts that pass through said fastened portions (34a, 34b, 34c) in said axial direction, and characterized in that the other of said casing and said casing cover include a plurality of protrusion portions (42a, 42b, 42c, 42d; 242a, 243a, 242b, 243b, 242c, 243c; 342a, 342b, 342c; 442a, 442b, 442c) provided in respective portions of an inner wall surface of said other of said casing and said casing cover which surround said stator core; said protrusion portions (42a, 42b, 42c, 42d; 242a, 243a, 242b, 243b, 242c, 243c; 342a, 342b, 342c; 442a, 442b, 442c) protrude from the inner wall surface of the cover toward the outer circumferential surface of the stator core, wherein said respective portions of the inner wall surface in which said protrusion portions (42a, 42b, 42c, 42d; 242a, 243a, 242b, 243b, 242c, 243c; 342a, 342b, 342c; 442a, 442b, 442c) are provided are opposed to the stator core in said axial direction, wherein said protrusion portions (42a, 42b, 42c, 42d; 242a, 243a, 242b, 243b, 242c, 243c; 342a, 342b, 342c; 442a, 442b, 442c) protrude toward said stator core so as to restrain said stator core from being inclined in directions away from said axis of the stator core toward said fastened portions (34a, 34b, 34c). a tubular-shaped stator core constituted by a plurality of steel sheets that are laminated on each other; a casing including an outer circumferential wall and a bottom wall, and storing therein one of opposite end portions of said stator core which are opposite to each other in an axial direction of said stator core; a casing cover including an outer circumferential wall and a bottom wall, and storing therein the other of said opposite end portions of said stator core, said casing cover being fixed to said casing; and a rotor disposed inside said stator core so as to be rotated about an axis of said stator core, wherein said stator core includes a plurality of fastened portions (34a, 34b, 34c) provided in respective portions of an outer circumferential surface of said stator core which are spaced apart from each other in a circumferential direction of said stator core, said fastened portions (34a, 34b, 34c) protruding outwardly in a radial direction of said stator core, said stator core being fastened at said fastened portions (34a, 34b, 34c) to said bottom wall of one of said casing and said casing cover, through fastening bolts that pass through said fastened portions (34a, 34b, 34c) in said axial direction, and characterized in that the other of said casing and said casing cover include a plurality of protrusion portions (42a, 42b, 42c, 42d; 242a, 243a, 242b, 243b, 242c, 243c; 342a, 342b, 342c; 442a, 442b, 442c) provided in respective portions of an inner wall surface of said other of said casing and said casing cover which surround said stator core; said protrusion portions (42a, 42b, 42c, 42d; 242a, 243a, 242b, 243b, 242c, 243c; 342a, 342b, 342c; 442a, 442b, 442c) protrude from the inner wall surface of the cover toward the outer circumferential surface of the stator core, wherein said respective portions of the inner wall surface in which said protrusion portions (42a, 42b, 42c, 42d; 242a, 243a, 242b, 243b, 242c, 243c; 342a, 342b, 342c; 442a, 442b, 442c) are provided are opposed to the stator core in said axial direction, wherein said protrusion portions (42a, 42b, 42c, 42d; 242a, 243a, 242b, 243b, 242c, 243c; 342a, 342b, 342c; 442a, 442b, 442c) protrude toward said stator core so as to restrain said stator core from being inclined in directions away from said axis of the stator core toward said fastened portions (34a, 34b, 34c).