To provide an electric rotary machine capable of high quality rotary driving with excellent durability by effectively reducing demagnetization of a permanent magnet.

An electric rotary machine includes a stator 11 having a plurality of teeth 15 facing a rotor 12, and a plurality of slots 18 as spaces each for winding a coil around the teeth, the rotor having a pair of permanent magnets 16 for applying magnetic force to the teeth, the magnets being embedded in the rotor in a V shape. When a pair of the permanent magnets in the rotor, corresponding to six slots in the stator, is defined as one magnetic pole, there are formed adjustment grooves 21 in the middle of magnetic paths of magnetic fluxes produced by supplying power to the coil, the magnetic fluxes flowing to demagnetization regions A1 produced in the permanent magnets, as magnetic resistance increasing regions for increasing magnetic resistance, the grooves including deepest portions 21a positioned 56° (an electrical angle) equally away from a d-axis passing through the center of the one magnetic pole in forward and backward directions, so that a width of each of the grooves is equal to that of each of facing teeth.