A structure and operation method of a spin device using a magnetic domain wall movement by spin orbit torque are provided. It is possible to invert the magnetization of free layer of the device at a low value of current by using the spin orbital torque, and the structure of the device is simpler than that of the conventional CMOS. Further, a spin synapse device to which a free layer of multiaxial anisotropy is applied in addition to movement of a magnetic domain wall is provided. Since the magnetoresistance can be adjusted according to the angle of the pinned layer and the free layer, it is easy to apply multi-bit and it can be applied to artificial synapse technology.