The magnetic sensor of the invention has an element portion that is elongate, that exhibits magnetoresistive effect and that has a magnetically sensitive axis in a direction of a short axis thereof. The element portion is non-oval and can be arranged in an imaginary ellipse, wherein the imaginary ellipse has a major axis that connects both ends of the element portion with regard to a direction of a long axis thereof to each other and a minor axis that connects both ends of the element portion with regard to a direction of the short axis thereof to each other, as viewed in a direction that is perpendicular both to the short axis and to the long axis of the element portion.