A case of neuroleptic malignant syndrome (NMS) in a 64-year-old man with cancer of the soft palate is reported. During haloperidol treatment for delirium, the patient showed consciousness disturbance with extrapyramidal signs. With discontinuation of haloperidol and replacement by dantrolene and bromocriptine, the patient recovered completely. Although major tranquilizers are widely used in clinical oncology to manage symptoms, NMS has been rarely reported in cancer patients, presumably because of lack of awareness. Early recognition of NMS and prompt treatment may improve the potentially fatal outcome.