The Chernobyl liquidators were the civil and military personnel who were called upon to deal with consequences of the 1986 Chernobyl nuclear disaster in the Soviet Union on the site of the event.

The colloquial term "liquidator" (Ukrainian: ліквідатор, Belarusian: ліквідатар, Russian: ликвида́тор, likvidator) originates from the Soviet official definition "участник ликвидации последствий аварии на Чернобыльской АЭС" (uchastnik likvidatsii posledstviy avarii na Chernobylʹskoy AES, literally "participant in liquidation of the Chernobyl NPP accident consequences") which was widely used to describe the liquidators' activities regarding their employment, healthcare and retirement. This exact phrase is engraved on the Soviet medals and badges awarded to the liquidators.