A magnetic sensor includes an MR element and a pair of magnets. The MR element includes a magnetization pinned layer having a magnetization pinned in a direction parallel to an X direction, a free layer having a magnetization that varies depending on an X-direction component of an external magnetic field, and a nonmagnetic layer interposed between the magnetization pinned layer and the free layer. The magnetization pinned layer, the nonmagnetic layer and the free layer are stacked to be adjacent in a Y direction. The free layer receives an interlayer coupling magnetic field in a direction parallel to the X direction resulting from the magnetization pinned layer. The pair of magnets applies a bias magnetic field to the free layer. The bias magnetic field includes a first component in a direction opposite to that of the interlayer coupling magnetic field and a second component in a Z direction.