The Japan Democratic Party was a conservative political party in Japan which was active from 1947 to 1950 and from 1954 to 1955. The party was founded by merging Inukai Takeru's Japan Progressive Party with Hitoshi Ashida's faction of the Liberal Party of Japan, and party leader Ashida served as Prime Minister for seven months in 1948. In 1948, part of the Democratic Party's members joined the reincarnated Liberal Party, and the remainder joined the National Democratic Party of Japan in 1950. The JDP was reincarnated in November 1954 as a merger of another splintergroup of the Liberal Party with the liberal Kaishinto party, and, in November 1955, it merged with the Liberal Party to form the Liberal Democratic Party.
The Japan Democratic Party was a centrist party that aimd to bridge the gap between the conservative and socialist parties through emphasizing democratic reforms, civil liberties, and social welfare policies.