A reluctance type synchronous motor comprises: a stator with a plurality of slots placed at an even pitch angle wherein stored inside each slot is a stator winding for creating stator magnetic poles with a predetermined phase alternating current being supplied thereto. A rotor sustained by a shaft and changing magnetic reluctance in its circumferential direction by inclusion inside of a plurality of magnetic isolating portions creates desired magnetic poles. At least one of the central angles between magnetic poles created at the rotor is shifted from the other central angles so that torque ripples during rotation can be reduced.