The 2003 Liberal Democratic Party presidential election was held on 20 September 2003 to elect the next president of the Liberal Democratic Party of Japan, as the term of incumbent LDP president and Prime Minister of Japan, Junichiro Koizumi, was ending at the end of that month. Voting among party members of the prefectural chapters was held from September 8 to 19.
Koizumi easily won reelection, securing a majority of support. Successful to Koizumi's win were his support from the prefectural chapter members and members of the Mitsuo Horiuchi and Ryutaro Hashimoto factions. The election was mainly seen as a choice of who would be the party "face" in the upcoming House of Representatives election and House of Councillors election. After winning the election, Koizumi appointed a new cabinet, including future Prime Minister Shinzo Abe as Chief Cabinet Secretary. On October 10, Koizumi dissolved the House of Representatives and set the general election date for November 9.
Party regulations require candidates to have the written support at least 20 Diet members, known as recommenders, to run.
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