Pervomaisk (Ukrainian: Первомайськ, IPA: [perwoˈmɑjsʲk] ⓘ; Russian: Первомайск) is a city in Mykolaiv Oblast, Ukraine.

The city was formed in 1919 after the Bolshevik victory in the Ukrainian-Soviet war, as a result of the merger of three historic towns in the area.

[8][7] The history Olviopol dates back to 1676, when the Orlyk (Орлик) fortress was founded by the Cossacks in protection against Crimean Tatar raids.

[7] In the late 19th century, despire its village status, it had two breweries and an iron factory, and its population exceeded 4,000.

In World War II, Pervomaisk was occupied by the Axis Powers in 1941 and was divided between German occupation authorities on the east bank (Bohopol and Olviopol) and the Romanian-occupied region of Transnistria to the west (Holta).

Elements of the Soviet Strategic Rocket Forces arrived in Pervomaisk for the first time as early as June 1960, and were present throughout the Cold War.

[14] In 2023, the working group of the National Commission on State Language Standards [uk] included Pervomaisk in the list of settlements in Ukraine that contain words with the root "Pervomai" ("1 May", the International Workers' Day of the Soviet Union) and can be renamed as part of decommunization and derussification campaigns in Ukraine.

The RT-23UTTKh intercontinental ballistic missile silos based at Pervomaisk were destroyed, partially with Nunn–Lugar Cooperative Threat Reduction programme funding, during the 1990s.