The Toei 6300 series is an electric multiple unit (EMU) commuter train type operated by the Tokyo Metropolitan Bureau of Transportation (Toei) on the Toei Mita Line in Tokyo, Japan. Introduced into service on 23 June 1993, a total of 37 six-car trainsets were built by Kawasaki Heavy Industries and Kinki Sharyo between 1993 and 2000 to replace the non-air-conditioned Toei 6000 series.

The Toei Mita Line is a subway line of the Tokyo Metropolitan Bureau of Transportation (Toei) network in Tokyo, Japan. The line runs between Nishi-Takashimadaira in Itabashi and Meguro in Shinagawa. Trains continue with direct service into the Meguro Line of Tokyu Corporation for Hiyoshi. The portion between Shirokane-Takanawa and Meguro is shared with the Tokyo Metro Namboku Line.