Yukio Hatoyama (鳩山 由紀夫, Hatoyama, Yukio?, born 11 February 1947) is a Japanese politician who served as Prime Minister of Japan between 16 September 2009 and 2 June 2010, and was the first ever Prime Minister from the modern Democratic Party of Japan.
First elected to the House of Representatives in 1986, Hatoyama became President of the DPJ, the main opposition party, in May 2009. He then led the party to victory in the August 2009 general election, defeating the long-governing Liberal Democratic Party (LDP). He represents the 9th district of Hokkaidō in the House of Representatives.
Hatoyama comes from a prominent Japanese political family which has been likened to the Kennedy family of the United States.