Originally Posted by AlwaysAisle

Tokyo does not have official China town but immediate northwest area of Ikebukuro station is known to have Chinese restaurants which are frequented by Chinese expatriates living in Tokyo. The map of Ikebukuro Chinatown (PDF format, in Japanese) shows locations of Chinese restaurants frequented by Chinese living in Tokyo. If you want more authentic Chinese, not Japanese-Chinese, then restaurants in Ikebukuro may satisfy your palate.