Siemiatycze County is a unit of territorial administration and local government (powiat) in Podlaskie Voivodeship, north-eastern Poland, on the border with Belarus. It came into being on January 1, 1999, as a result of the Polish local government reforms passed in 1998. Its administrative seat and largest town is Siemiatycze, which lies south of the regional capital Bialystok. The only other town in the county is Drohiczyn, lying west of Siemiatycze.