The utility model relates to a generator rotor support structure, including a drum, equidistant the welding of week side of drum is equipped with 7 fore -and -aft muscle that stand, connecting plate fixed connection that upper end between per two adjacent upright muscle and lower extreme passed through an arcuation respectively. The utility model has the advantages of through the stability of the spider assurance generator rotor of mechanism subassembly, it is skew to prevent that the rotor from taking place.