Mykolaivka was founded in 1791.[3][4] The area was settled after 1792, when the lands between the Southern Bug and the Dniester were transferred to Russia according to the Iasi Peace Treaty. Until mid-20th century, it was known as Mykolaivka Druha (Ukrainian: Миколаївка Друга, Russian: Николаевка Вторая).[3]
Until 18 July 2020, Mykolaivka was the administrative center of Mykolaivka Raion. The raion was abolished in July 2020 as part of the administrative reform of Ukraine, which reduced the number of raions of Odesa Oblast to seven. The area of Mykolaivka Raion was merged into Berezivka Raion.[5][6]
Until 26 January 2024, Mykolaivka was designated urban-type settlement. On this day, a new law entered into force which abolished this status, and Mykolaivka became a rural settlement.[7]