ABSTRACT Although multiple cortical tubers are a hallmark of tuberous sclerosis complex (TSC), seizures often originate from a single tuber, making excisional surgery a therapeutic option for intractable patients. To assess the role of ictal single photon emission computed tomography (SPECT) in defining the epileptogenic tuber, we reviewed videoelectroencephalography (V/EEG) data, magnetic resonance imaging (MRI) and SPECT scans of 15 patients (aged 3 months to 15 years, mean 5.1) with medically resistant partial seizures and TSC. SPECT scans were performed using Tc‐99m‐hexamethylpropyleneamine oxime (HMPAO) injected within 30 seconds of electrographic seizure onset and were graded on a scale from 1 to 5 (1 weakly perfused, 5 strongly perfused). The scalp EEG revealed localized seizure origin in ten patients; five had concordant hyperperfused SPECT regions consisting of comma‐shaped areas surrounding hypoperfused areas in the candidate tuber. Strongly hyperperfused regions (grade 3‐5) were noted in two patients whose ictal EEG patterns were characterized by sustained, rhythmic fast activity or spiking. The other five patients had nonlocalizing or poorly sustained ictal EEG patterns; one patient in this group had focal hyperperfusion. Invasive EEG recordings in two patients revealed propagated EEG patterns that correlated with the ictal SPECT findings. These findings indicate a strong correlation between ictal SPECT and ictal scalp EEG, especially when there are sustained rhythmic fast ictal EEG patterns.