Clozapine is an atypical antipsychotic agent that is more effective than the typical neuroleptics in the treatment of refractory schizophrenia. Recently, there has been an increased recognition of the association of clozapine with myocarditis and cardiomyopathy. Commonly used diagnostic tests have limited sensitivity in diagnosing this potentially life-threatening complication. Here we report a case of 36-year-old male patient who developed fever, tachycardia, and dyspnea after introduction of clozapine. By clinical evaluation and laboratory test we diagnosed the patient with myocarditis and treated him successfully. To our knowledge this is the first case report of clozapine-induced myocarditis in Korea.