We report our experience using lidocaine to determine the epileptic focus in a case of refractory status epilepticus associated with an aberrant intracranial shunt tube. Pentobarbital anesthesia rapidly suppressed convulsions. However, whenever the pentobarbital was decreased, the status epilepticus was resumed. The seizure looked primarily generalized both clinically and electroencephalographically, but EEG monitoring with intravenous administration of lidocaine demonstrated that the ictal waves began from the right anterotemporal area, where the shunt valve and tube were placed. Removal of the shunt tube and the surrounding scar tissue eliminated status epilepticus. Our result suggests the excellent efficacy of lidocaine to distinguish secondarily generalized status epilepticus from primarily generalized one.