Gmina Siemkowice is a rural gmina (administrative district) in Pajęczno County, Łódź Voivodeship, in central Poland. Its seat is the village of Siemkowice, which lies approximately 9 kilometres (6 mi) north-west of Pajęczno and 76 km (47 mi) south-west of the regional capital Łódź.
The gmina covers an area of 97.4 square kilometres (37.6 sq mi), and as of 2006 its total population is 5,016.