Two patients presented with a complaint of frequent sudden arousals during sleep followed by tachypnea and palpitation associated with stiffness in the upper extremities in one case and by elevation of the left lower limb in the other. All night video-electroencephalogram (EEG) polysomnography (VPSG) confirmed the diagnosis of seizure arising from the supplementary motor area (SMA seizure) in both cases. Carbamazepine (CBZ) produced remarkable improvement both in clinical seizures and in their subjective sleep quality. Repeated polysomnography after treatment showed a clear improvement in sleep architecture with higher percentages of slow wave sleep. SMA seizure could disturb nocturnal sleep and is one of the important differential diagnoses for a patient complaining of frequent arousals associated with motor disturbance during sleep.