Methylcobalamin can be used to treat peripheral facial palsy by nourishing the facial nerve and promoting the recovery of the facial nerve. Peripheral facial palsy is caused by damage to the facial nerve, which may be caused by wind, cold or viral infection, resulting in edema and damage to the facial nerve, and causing facial expression muscle paralysis. In the acute stage, mecobalamin should be given to nourish the facial nerve, and the treatment effect is still good. At the same time, other treatment methods should be used, such as dexamethasone to reduce the facial nerve edema, or sodium heptaerythrone, together with oral mecobalamin or mecobalamin intramuscular injection, so as to achieve better treatment effect. During the recovery period of facial palsy, oral methylcobalamin can be used to nourish the facial nerve for treatment. The later stage of facial palsy is mainly treated by acupuncture, cupping and bloodletting to help the recovery of facial palsy patients.