Recently, various diagnostic modalities revealed the characteristic abnormalities in transient global amnesia (TGA). We described two TGA patients with focal lesions in the right hippocampus. One patient showed bilateral temporal spike-and-wave on EEG and contralateral temporal hyperperfusion on SPECT. The other exhibited contralateral temporal sharp waves and ipsilateral temporal hypoperfusion. Our patients suggest that bilateral dysfunction of the medial temporal lobe is important for developing TGA. Multimodal diagnostic approach is required to clarify this phenomenon.