Paraneoplastic syndrome is not curable and most patients have a poor prognosis. Paraneoplastic syndrome refers to the damage of central nervous system and autonomic nervous system caused by autoimmune reaction secondary to malignant tumors, and patients will show corresponding symptoms. Paraneoplastic syndrome is relatively rare in the clinic, and the treatment is mainly aimed at the primary disease. If the site of the tumor is found, surgical resection of the tumor or radiotherapy or chemotherapy may be effective for patients with paraneoplastic syndrome. Patients should also be given immunotherapy and symptomatic antiepileptic and neuroprotective drugs.