Shinjirō Koizumi

Junichiro Koizumi was born in 1982. His father is former Prime Minister Junichiro Koizumi. His mother is Kayo Miyamoto; the two divorced in 1982. Junichiro Koizumi and his older brother, Koutarou Koizumi, were raised by their father from a young age. His brother has entered the entertainment industry and has not shown a clear interest in politics. Junichiro Koizumi has a solid academic background; he graduated in March 2004 from Kanto Gakuin University with a degree in Economics and earned a master's degree in Political Science from Columbia University in the United States.

In May 2006, he became a researcher at the Center for Strategic and International Studies (CSIS) in the US. Later, in September 2007, he entered politics, serving as a member of the House of Representatives, and was nominated as a Liberal Democratic Party (LDP) candidate with the support of Junichiro Koizumi. In September 2008, Junichiro Koizumi announced his retirement from politics, and his political legacy was inherited by Junichiro Koizumi. That same year, he was elected for the first time as a member of the House of Representatives representing Kanagawa's 11th district as a substitute candidate for the LDP.

During his political career, Junichiro Koizumi has held several important positions, including in October 2011 as the Director of the LDP Youth Bureau, in September 2013 as Parliamentary Senior Vice Minister of the Cabinet Office and Senior Vice Minister for Restoration, in October 2015 as President of the LDP Agriculture, Forestry and Fisheries Committee, in August 2017 as the First Deputy Secretary-General of the LDP, and in October 2018 as Minister of Health, Labour and Welfare. In September 2020, he was appointed Japan's Minister of the Environment and was reappointed in 2021, also serving as the Minister in charge of Climate Change. On October 4, 2021, Japan's Cabinet resigned en masse during an extraordinary session. Subsequently, in November 2021, he was appointed acting Secretary-General of the LDP General Council, and in April 2022, he became the President of the Kanagawa Prefectural Federation.

Since September 2022, Junichiro Koizumi has served as Vice Chairman of the LDP's Diet Strategy Committee, and from November 2023, he has been the Chief Director of the House of Representatives' Security and Defense Committee, ascending to Chairmanship in January 2024. In September 2024, he was appointed Chair of the LDP Election Strategy Committee. In October 2024, he was elected as the member of the 50th House of Representatives but voluntarily resigned from the position of Election Strategy Chair on October 28 of the same month.

Regarding his family, his father is former Prime Minister Junichiro Koizumi, and his mother is Kayo Miyamoto (raised by his father after their divorce). He has an older brother, Koutarou Koizumi. Personal life-wise, he married actress Masami Takinouchi in August 2019 and has children.