Mykolaivka or Nikolaevka (Ukrainian: Миколаївка; Russian: Николаевка) is a rural settlement in the west of Odesa Oblast, Ukraine.

[1] Mykolaivka is located on the banks of the Chychykleia River, a right tributary of the Southern Bug, at the border with Mykolaiv Oblast.

[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).

On this day, a new law entered into force which abolished this status, and Mykolaivka became a rural settlement.