The frontal lobe seizures present variable clinical and electroencephalographic features that play some difficulties in the presurgical work-up for epilepsy. The aim of the present study is to determine the role of ictal and interictal SPECT in the localization of the epileptogenic zone in frontal lobe epilepsies. We evaluated 13 patients, 6 men and 7 women, with mean age of 16yr, and with medically intractable frontal lobe seizures. All patients were submitted to ictal SPECT and 11 also to interictal scans. Ictal SPECT studies were contributive in 54% of patients, and nonlateralized and nonlocalized, or contralateralized in the remaining patients. Interictal SPECT showed normal perfusion in 45,5% of patients, hypoperfusion localized in the suspected epileptogenic zone in 45,5%, and diffuse findings in the other 9%. We conclude that the sensitivity of ictal and interictal SPECT studies in frontal lobe epilepsies is lower than that for temporal lobe seizures, thus confirming previous data.