Leonid Danylovych Kuchma (Ukrainian: Леонід Данилович Кучма, IPA: [leoˈn⁽ʲ⁾id dɐˈnɪlowɪtʃ ˈkutʃmɐ]; born 9 August 1938) is a Ukrainian politician who was the second president of Ukraine, serving from 19 July 1994 to 23 January 2005. The only president of Ukraine to serve two terms, his presidency was marked by economic stabilization and an improvement in Russia–Ukraine relations, but at the same time was accompanied by democratic backsliding and growth of the influence of Ukrainian oligarchs, as well as several scandals.

After a successful career in the machine-building industry of the Soviet Union, Kuchma began his political career in 1990, when he was elected to the Verkhovna Rada (the Ukrainian parliament); he was re-elected in 1994. He served as Prime Minister of Ukraine between October 1992 and September 1993. Kuchma took office after winning the 1994 presidential election against his rival, incumbent President Leonid Kravchuk. Kuchma won re-election for an additional five-year term in 1999. Corruption accelerated after Kuchma's election in 1994, but in 2000–2001, his power began to weaken in the face of exposures in the media.

Kuchma's administration began a campaign of media censorship in 1999, leading to arrests of journalists, the death of Georgiy Gongadze, and the subsequent Cassette Scandal and mass protests. The Ukrainian economy continued to decline until 1999, whereas growth was recorded since 2000, bringing relative prosperity to some segments of urban residents. During his presidency, Ukrainian-Russian ties began to improve. Kuchma declined to seek a third term in office, instead supporting Party of Regions candidate Viktor Yanukovych for the 2004 election. Following public protests over the alleged electoral fraud which escalated into the Orange Revolution, Kuchma took a neutral stance and was a mediator between Viktor Yushchenko and Viktor Yanukovych. Between 2014 and 2020, Kuchma was a special presidential representative of Ukraine at the quasi peace talks regarding the ongoing War in Donbas.

Kuchma's legacy has proven controversial, and he has been described as authoritarian by various sources. Widespread corruption and media censorship under Kuchma's administration continue to have an impact on Ukraine today, and he has been accused of promoting oligarchism.

Leonid Danylovych Kuchma was born in the village of Chaikyne in rural Chernihiv Oblast on 9 August 1938. His father, Danylo Prokopovych Kuchma (1901–1942) was wounded in World War II and eventually died of his wounds in the field hospital #756 (near the village of Novoselytsia) when Leonid was four. His mother Paraska Trokhymivna Kuchma worked on a kolkhoz.

Kuchma attended the Kostobobriv general education school in the neighboring Semenivka Raion. Later he enrolled in Dnipropetrovsk National University and graduated in 1960 with a degree in mechanical engineering (majoring in aerospace engineering), eventually becoming a candidate of technical sciences. In 1960 he joined the Communist Party of Soviet Union.

After graduation, Kuchma worked in the field of aerospace engineering for the Yuzhnoye Design Bureau in Dnipropetrovsk. At 28 he became a testing director for the Bureau deployed at the Baikonur cosmodrome.

Some political observers suggested that Kuchma's early career was significantly boosted by his marriage to Lyudmyla Talalayeva, an adopted daughter of Gennadiy Tumanov, the Yuzhmash chief engineering officer and later the Soviet Minister of Medium Machine Building.