A rotor structure comprising a rotor coil for generating a magnetic flux, a pole core which covers the rotor coil and consists of a first pole core body and a second pole core body, each having a plurality of claw-like magnetic poles which are mated with each other, magnets provided on both sides of each of the claw-like magnetic pole for suppressing the leakage of a magnetic flux between adjacent claw-like magnetic poles, and reinforcements for holding the magnets in such a manner that the magnets are inclined so that the interval between the magnets becomes larger on the outer side than on the inner side. This rotor structure can reduce centrifugal force applied to the magnets.