The Mitsubishi i is a kei car from automaker Mitsubishi Motors, first released in January 2006, twenty eight months after its debut at the 2003 Frankfurt Motor Show. It is the first four-door automobile since the 1960s to employ a "rear midship" setup with the engine behind the passengers, in an attempt to improve safety and interior space without enlarging the overall exterior.

Kei car is the smallest category of Japanese, expressway-legal motor vehicles. 'Kei' is diminutive for kei-jidōsha,, "light automobile" or "compact automobile". With restricted dimensions and engine specifications, owners benefit firstly from lower taxes and insurance rates which lead to a lower overall cost of ownership. And in most rural areas, importantly, they were also exempted from the general Japanese shako shōmeisho (車庫証明書) parking-space ownership requirement to legally buy a motor vehicle at all, as street parking is generally restricted in Japan. Japan's carmakers also make microvans and kei trucks within this legal category.