Gmina Rząśnia is a rural gmina (administrative district) in Pajęczno County, Łódź Voivodeship, in central Poland. Its seat is the village of Rząśnia, which lies approximately 9 kilometres (6 mi) north of Pajęczno and 70 km (43 mi) south-west of the regional capital Łódź.
The gmina covers an area of 86.37 square kilometres (33.3 sq mi), and as of 2006 its total population is 4,802.
In the municipality of Rząśnia, there is a brown Coal Mine