Tokyo (東京 lit. "The capital of the east") is the city in which Doraemon, Nobita and friends live. The unnamed neighborhood that they live in appears to not be very civilized but still lively. Most of the episodes and chapters take place in this town and nearby.
Tokyo is based on real-life Tokyo, Japan. The fictional town that Nobita and friends live in was stated to be based in Nerima Ward according to Suneo's address (Tokyo, Nerima Ward, Tsukimidai, Susukigahara, 3-10-5) as shown in Chapter 272:Chain Letter Syndicate.