The invention relates to a claw pole type pole-changing generator rotor and relates to a generator rotor. The claw pole type pole-changing generator rotor comprises a rotating shaft, a rotor excitation component, a slip ring component 1 and a slip ring component 2. When the generator rotor is applied to a pole-changing automobile generator, the polarity of claw pole 1 and claw pole 2 magnetic poles are simultaneously changed according to the rotation speed of the generator rotor, so the number of the magnetic poles is larger when the generator rotor is in a low speed operation state, and the number of the magnetic poles is smaller when the generator rotor is in a high speed operation state. When the generator rotor is in the high speed operation state, the number of rotor magnetic poles isreduced, the frequency of alternating current generated by a stator winding of a stator component used with the generator rotor is reduced, the stator core eddy current loss is reduced, and the efficiency of the automobile generator is improved.