Gmina Kuźnica is a rural gmina (administrative district) in Sokółka County, Podlaskie Voivodeship, in north-eastern Poland, on the border with Belarus.

Its seat is the village of Kuźnica, which lies approximately 16 kilometres (10 mi) north-east of Sokółka and 54 km (34 mi) north-east of the regional capital Białystok.

The gmina covers an area of 133.41 square kilometres (51.5 sq mi), and as of 2006 its total population is 4,277.

[1] Gmina Dąbrowa Białostocka is divided into 30 sołectwa.

[2] Gmina Kuźnica is bordered by the gminas of Nowy Dwór, Sidra and Sokółka.