A stepping motor 10 comprises a rotor 3 of a permanent magnet 2 having multiple poles magnetized in the circumferential direction, and multiple stator yokes 5a and 5b disposed on the outer periphery of this rotor 3 to form a multiple-phase field magnet of multiple phases. Detent torque of the stepping motor is reduced either by reducing a cross-sectional area of a portion, which leads to a magnetic pole surface 51a of the stator yoke, to be less than an area of the magnetic pole surface 51a, or by disposing an intermediate magnetic substance 9 which is magnetically independent of the stator yokes 5a and 5b on both sides thereof. In addition, a stator yoke 5 is formed of two-divided members and both divided members 51 and 52 are connected to each other inside a winding bobbin 7 so as to increase the quality and the workability of assembly.