Kharkiv (Ukrainian: Ха́рків, IPA: [ˈxɑrkiu̯] (listen)), also known as Kharkov (Russian: Харькoв, IPA: [ˈxarʲkəf]), is the second-largest city and municipality in Ukraine. Located in the northeast of the country, it is the largest city of the historic region of Sloboda Ukraine. Kharkiv is the administrative centre of Kharkiv Oblast and of the surrounding Kharkiv Raion. It has a population of 1,421,125 (2022 est.).

Kharkiv was founded in 1654 as a fortress, and grew to become a major centre of industry, trade, and Ukrainian culture in the Russian Empire. At the beginning of the 20th century, the city was predominantly Russian in population, but as industrial expansion drew in further labor from the distressed countryside, and as the Soviet Union moderated previous restrictions on Ukrainian cultural expression, Ukrainians became the largest ethnic group in the city by the eve of World War II. From December 1919 to January 1934, Kharkiv was the first capital of the Ukrainian Soviet Socialist Republic.

Kharkiv is a major cultural, scientific, educational, transport and industrial centre of Ukraine, with numerous museums, theatres and libraries, including the Annunciation and Dormition cathedrals, the Derzhprom building in Freedom Square, and the National University of Kharkiv. Industry plays a significant role in Kharkiv's economy, specialised primarily in machinery and electronics. There are hundreds of industrial facilities throughout the city, including the Morozov Design Bureau, the Malyshev Factory, Khartron, Turboatom, and Antonov.

In March and April 2014, security forces and counter-demonstrators defeated efforts by Russian-backed separatists to seize control of the city and regional administration. Kharkiv was a major target for Russian forces in the northeastern Ukraine campaign during the 2022 Russian invasion of Ukraine before they were pushed back to the Russia-Ukraine border. The city remains under intermittent Russian fire.