Hayato Ikeda (池田 勇人, Ikeda Hayato; 3 December 1899 – 13 August 1965) was a Japanese politician who served as prime minister of Japan from 1960 to 1964. He is best known for his Income Doubling Plan, which promised to double the size of Japan's economy in 10 years, and for presiding over the 1964 Tokyo Olympics.

Born in Hiroshima Prefecture, Ikeda studied law at Kyoto Imperial University and entered the Ministry of Finance in 1925, working there for the next two decades. After the war, he was first elected to the National Diet in 1947 and served as finance minister from 1949 to 1952 under Shigeru Yoshida, being responsible implementing an economic stabilization program. Ikeda briefly headed the Ministry of International Trade and Industry in 1952, but resigned after a no-confidence motion. He returned as finance minister under Tanzan Ishibashi from 1956 to 1957, and as international trade and industry minister from 1959 to 1960.

Ikeda succeeded Nobusuke Kishi as president of the Liberal Democratic Party (LDP) and prime minister in 1960, following Kishi's resignation amid the massive Anpo protests against the US-Japan Security Treaty. Seeking to redirect the nation's energies away from social conflict and in the direction of economic growth, Ikeda announced his Income Doubling Plan and helped Japan to double its GDP in a period of just seven years. During his tenure, Ikeda worked to repair the rift in U.S.–Japan relations and to ease the domestic political divisions which had been exacerbated by the recent protests, played an important role in settling the Miike Struggle, and oversaw the successful 1964 Olympic Games before resigning due to ill health.

Ikeda was born on 3 December 1899, in Yoshina, Hiroshima Prefecture (present-day Takehara, Hiroshima), the youngest child of Goichirō Ikeda and his wife Ume. He had six siblings.

He attended Kyoto Imperial University and joined the Ministry of Finance following graduation in 1925. While at the ministry, he served as the head of the local tax offices in Hakodate and Utsunomiya. During his time in the latter role, in 1929, he contracted pemphigus foliaceus and went on sick leave for two years, formally resigning in 1931 once his sick leave had run out. The condition was cured by 1934. He briefly considered accepting a position at Hitachi, but returned to the Ministry of Finance in December 1934 to head a tax office in Osaka. Ikeda remained within the ministry through the end of World War II, eventually becoming Vice Minister of Finance under Prime Minister Shigeru Yoshida in 1947.

Ikeda resigned from the Ministry of Finance in 1948 and won a seat in the House of Representatives, representing a portion of Hiroshima Prefecture, in the general election of 23 January 1949. He was a part of the liberal group that established the Democratic Liberal Party, a forerunner of the current Liberal Democratic Party. Along with Eisaku Satō, Ikeda was an understudy of Shigeru Yoshida early in his career, and was called an "honor student" for his commitment to the ideas presented in the Yoshida Doctrine, although he was a strong personality himself.

He was appointed Minister of Finance on 16 February 1949 by Prime Minister Shigeru Yoshida, and on 7 March announced the Dodge Line monetary policy with American occupation advisor Joseph Dodge. He visited the United States in 1950 to begin preparations for U.S.–Japan security cooperation following the end of the occupation. In 1951, he oversaw the formation of the Development Bank of Japan and Japan Bank for International Cooperation.

In the 1950s, Ikeda developed a reputation as a distant and haughty technocrat unsympathetic to the concerns of ordinary people following a series of verbal gaffes. In a December 1950 Upper House Budget Committee meeting, for example, Ikeda suggested that poor people should eat more barley, rather than expensive white rice. This was reported in the press as "Let the poor eat barley!" Ikeda then became Minister of International Trade and Industry following a cabinet reshuffle in 1952, but was forced to resign less than one month later after he was reported to have said in the Diet, in reference to efforts to curb rampant inflation, "even if five or ten small businessmen commit suicide, it can't be helped." Nevertheless, Ikeda remained a senior LDP lawmaker in various party posts, and returned to the Cabinet as Minister of Finance in December 1956. He then became minister without portfolio in June 1958, and Minister of International Trade and Industry in June 1959.