Gmina Dmosin is a rural gmina (administrative district) in Brzeziny County, Łódź Voivodeship, in central Poland. Its seat is the village of Dmosin, which lies approximately 14 km (9 mi) north of Brzeziny and 26 km (16 mi) north-east of the regional capital Łódź.
The gmina covers an area of 100.53 km2 (38.8 sq mi), and as of 2006 its total population is 4,671.