Gmina Siedlisko is a rural gmina (administrative district) in Nowa Sól County, Lubusz Voivodeship, in western Poland. Its seat is the village of Siedlisko, which lies approximately 8 kilometres south-east of Nowa Sól and 29 km south-east of Zielona Góra. The gmina covers an area of 92.19 square kilometres, and as of 2006 its total population is 3,492.