Tuberous sclerosis complex (TSC) has been known to present a high incidence (60-90%) of epilepsy due to cortical tubers. In 50 to 80% of the epilepsy patients with TSC, epileptic seizures become resistant against anti-epileptic medications. The multiple cortical tubers are considered to promote the wide epileptic network in a part of TSC patients. The extensive and disrupted epileptic network with the multiple tubers and abnormal cortices are highly correlated with their complicated epileptogenesis. In a subset of TSC patients, the distribution of epileptogenic zone can propagate from a single focus at the beginning of seizure history, to bilateral and multiple foci during the clinical course. We found that the laterality of spikes during rapid-eye-movement (REM) sleep despite of diffuse and multifocal spikes during non-REM sleep on the long-term video EEG monitoring related with the laterality of the epileptogenic hemisphere. Furthermore, the pattern of distribution of equivalent current dipoles on magnetoencephalography (MEG) can be applied to identify epileptogenic zone among multiple cortical tubers. This paper presents roles of pediatric neurologists to which patients are candidate for surgical treatments and when is the best to offer surgery; using the long-term video EEG and MEG.