The invention provides a highly efficient high-speed permanent magnetic synchronous motor, which relates to the technical field of motors, and the synchronous motor solves the problems of little leakage reactance, the great harmonic component of winding current and the high frequency loss of the stator and the rotor of a motor, which exist in the existing high-speed permanent magnetic synchronousmotor. The motor comprises a stator, a rotor and an air gap, and is of an inner rotor structure; the rotor comprises a permanent magnet, a permanent magnet sheath and a rotating shaft, and the statorcomprises a stator core and a winding; one side of the stator core, which is near a shaft center, has a plurality of cogging through holes opened along an axial direction, and the cogging through holes are used for embedding and placing the winding; the stator core can also adopt a split type, namely that the core is divided into a yoke core and a cogging core, the yoke core is cylindrical, the inside of the cogging core is cylindrical, and the external circumference of the cogging core has a plurality of coggings opened along an axial direction used for embedding and placing the winding; thecogging core is embedded into the yoke core to form the stator core. The synchronous motor can not only be used as a high-speed motor, but also be used as a high-speed generator, thereby having wide application prospect.