April 24, 2001 - Is elected president of the Liberal Democratic Party (LDP), defeating incumbent Ryutaro Hashimoto.
April 26, 2001 - Is named Japan's 86th prime minister.
September 20, 2003 - Is re-elected as president of the LDP.
November 19, 2003 - Is re-elected as prime minister of Japan.
September 21, 2005 - Is re-elected as prime minister.
June 30, 2006 - During a visit to the United States, Koizumi takes a private tour of Graceland with U.S. President George W. Bush, Lisa Marie Presley and Priscilla Presley.
September 26, 2006 - Steps down as prime minister and returns to the House of Representatives.
September 25, 2008 - Announces that he will not run for re-election in 2009 and that he is retiring from politics.
August 2009 - Shinjiro Koizumi wins the House of Representatives seat formerly held by his father, Junichiro Koizumi.
December 12, 2009 - The film "Mega Monster Battle: Ultra Galaxy Legends The Movie" is released. The character Ultraman King is voiced by Junichiro Koizumi.