The prognostic values of stapedius reflex (SR) test on peripheral facial palsy in an early stage were investigated based on the presence of SR and the restoration of the impaired SR in 76 cases with unilateral Bell's palsy.Results obtained from SR test are as follows. 1. In all cases except for one, SR restored within 4 months after the onset of palsy, not depending upon the severity of facial palsy. 2. An overall tendency revealed that the restoration of SR occurs rather earlier than the recovery of facial palsy, but only several cases showed a complete recovery of facial palsy without any signs of SR. 3. In cases with suprastapedial lesions, the earlier the restoration of SR, the more complete recovery of facial palsy can be achieved. 4. In the early stage (within 3 weeks after the onset of palsy), 35 out of 40 cases (88%) with signs of SR showed a good prognosis. Cases without any signs of SR, on the other hand, did not always show a poor prognosis. Therefore, SR measurements are complementary in the prognostic diagnosis on Bell's palsy in an early stage.