Rear wheel steering apparatus for vehicle

A rear wheel steering apparatus for a vehicle includes a housing (1) including a cylinder portion (10) and a connection cover (11), an electric motor (3a) housed in the housing (1), a speed reduction mechanism (3b) housed in the housing (1), a linear motion mechanism (3c) including a nut member (36) and a rod (2) for converting a rotation of the nut member (36) to a linear motion of the rod (2), the cylinder portion (10) including a stopper portion (10a, 14) provided at an inner surface of thereof between the electric motor (3a) and the speed reduction mechanism (3b), a cylindrical holding member (34) holding the speed reduction mechanism (3b) in the cylinder portion (10), and a bearing (37) supporting the nut member (36) for allowing the nut member (36) to rotate relative to the cylindrical holding member (34). The bearing (37) and the cylindrical holding member (34) are sandwiched between the stopper portion (10a, 14) and the connection cover (11) and the cylindrical holding member (34) is retained so as not to rotate relative to the cylinder portion (10).