An object of the present invention is to provide a magnetic sensor less subject to an environmental magnetic field. A magnetic sensor includes magnetic detection elements MR1 to MR4 positioned on a first plane P1 and a magnetic member 30A provided on a second plane P2. The magnetic member 30A includes first and second leg parts 41 and 42 and a first main body part 51 positioned between the first and second leg parts 41 and 42 so as to form a first space 61 between itself and the second plane P2. The magnetic detection elements MR1 to MR4 are covered with the first main body part 51. According to the present invention, magnetic field to be detected is collected to the first and second leg parts 41 and 42, and the magnetic detection elements MR1 to MR4 are covered with the first main body part 51, thereby allowing an environmental magnetic field acting as noise to bypass the magnetic detection elements MR1 to MR4 through the first main body part 51. Thus, influence of the environmental magnetic field can be reduced.