The utility model discloses a respirator for a transformer, belonging to equipment of the transformer. The respirator for the transformer comprises a body and an oil bowl, wherein the bottom end of the body is provided with a vent pipe, and the oil bowl is arranged at the bottom of the body and held with engine oil, a plurality of active alumina balls are placed in the oil bowl and outside the vent pipe; the vent pipe extends to the underneath of the oil face of the engine oil in the oil bowl. By adopting the respirator for the transformer, the oil bowl is not easy to break, and the service life of the respirator is prolonged.