Gmina Płaska is a rural gmina (administrative district) in Augustów County, Podlaskie Voivodeship, in north-eastern Poland, on the border with Belarus. Its seat is the village of Płaska, which lies approximately 20 kilometres (12 mi) east of Augustów and 88 km (55 mi) north of the regional capital Białystok.
The gmina covers an area of 373.19 square kilometres (144.1 sq mi), and as of 2019 its total population is 2,594.