In the late-stage idiopathic Parkinson's disease (IDP), comorbid conditions such as depression and drug-induced psychosis may be observed. A patient with Parkinson disease, major depression, and paranoid psychosis who developed neuroleptic malignant syndrome (NMS) as the result of the sudden termination of high-dose (1200 mg/d) levodopa treatment is presented in this report. Because the patient did not respond to other treatment modalities, electroconvulsive therapy (ECT) was applied, and a rapid improvement was observed both in the patient's NMS and also in Parkinson's and psychiatric symptoms, with no additional side effects other than transient post-ictal confusions. The application of ECT allowed the patient to remain stable for a 5-year period with a quite low dose of levodopa (300 mg/d). Later, the patient had two episodes of depressive and psychotic symptoms, which were again successfully treated with the ECT. We suggest that ECT might be an effective and life-saving therapy in patients with severe, drug-resistant NMS.