Dziadkowice is a village in Siemiatycze County, Podlaskie Voivodeship, in north-eastern Poland. It is the seat of the gmina (administrative district) called Gmina Dziadkowice. It lies approximately 14 km north of Siemiatycze and 66 km south of the regional capital Białystok. According to the 1921 census, the village was inhabited by 107 people, among whom 67 were Roman Catholic, 36 Orthodox, and 4 Mosaic. At the same time, 75 inhabitants declared Polish nationality, 32 Belarusian. There were 22 residential buildings in the village.