The April 9 tragedy (also known as Tbilisi Massacre, Tbilisi tragedy) refers to the events in Tbilisi, Georgian Soviet Socialist Republic, on April 9, 1989, when an anti-Soviet demonstration was dispersed by the Soviet Army, resulting in 20 deaths and hundreds of injuries. April 9 is now remembered as the Day of National Unity (Georgian: ეროვნული ერთიანობის დღე), an annual public holiday.

The anti-Soviet movement became more active in the Georgian SSR in 1988. Several strikes and meetings were organized by anti-Soviet political organizations in Tbilisi. The conflict between the Soviet government and Georgian nationalists deepened after the so-called Lykhny Assembly on March 18, 1989, when several thousand Abkhaz demanded secession from Georgia and restoration of the Union republic status of 1921–1931. In response, the anti-Soviet groups organized a series of unsanctioned meetings across the republic, claiming that the Soviet government was using Abkhaz separatism in order to oppose the pro-independence movement.