An adjustment holding portion (21) for adjusting the inclination of a guide shaft (22) guiding an optical pickup (2) in a radial direction with respect to a base (1) is mounted to the base (22) at a first supporting point (1n), a second supporting point (23) and a third supporting point (24). When the optical pickup (2) is located at a first position on the inner circumference side of the optical disk, the shaft-receiving portion (2c) of the optical pickup (2) is located on a line connecting the first supporting point and the second supporting point. When the optical pickup (2) is located at a second position on the outer circumference side of the optical disk, the shaft-receiving portion (2c) of the optical pickup (2) is located on a line connecting the first supporting point and the third supporting point.