Auditory event-related potentials (AERP) were elicited in 68 epileptic patients and 30 age-matched controls. Epileptic patients had significantly prolonged N2 and P300 (P3) latencies compared with controls. Seven patients were above the range of 3 standard deviations from the control mean values. Amongst epileptics, patients with temporal lobe epilepsy had significantly prolonged P3 latencies compared to patients with idiopathic generalized epilepsy. Patients with abnormal EEGs had significantly prolonged P3 latencies compared to those with normal EEGs. Patients on anticonvulsant monotherapy had shorter P3 latencies, compared to patients taking a combination of two or more anticonvulsants. Patients on shorter duration of treatment had less prolonged P3 latencies compared to those on longer anticonvulsant treatment.