A stator of a permanent magnet direct-drive wind power generator includes a stator support, a stator iron core, a blade side tooth pressing plate and a blade side surrounding plate. At least one comb tooth air inlet hole is provided on a side close to the rotor of the blade side surrounding plate, the comb tooth air inlet hole and the second air hole are connected respectively via an air guide pipe. A first spiral comb tooth mechanism is provided on a side, close to the rotor sealing ring, of the blade side surrounding plate, the first spiral comb tooth mechanism is in communication with the comb tooth air inlet hole. The first spiral comb tooth mechanism has first spiral comb teeth protruding into an annular gap formed by the blade side surrounding plate and the rotor sealing ring for generating an airflow with spiral motion.