Sięciaszka Trzecia [ɕɛnˈt͡ɕaʂka ˈtʂɛt͡ɕa] is a village in the administrative district of Gmina Łuków, within Łuków County, Lublin Voivodeship, in eastern Poland. It lies approximately 8 kilometres (5 mi) west of Łuków and 76 km (47 mi) north of the regional capital Lublin.