Aleksiejówka ([alɛkɕɛˈjufka]; Lithuanian: Aleksėjauka) is a village in the administrative district of Gmina Giby, within Sejny County, Podlaskie Voivodeship, in north-eastern Poland, close to the borders with Belarus and Lithuania.

From the 13th century to 1795, this village belonged to the Grand Duchy of Lithuania's Trakai Voivodeship.