Gmina Miastków Kościelny is a rural gmina (administrative district) in Garwolin County, Masovian Voivodeship, in east-central Poland. Its seat is the village of Miastków Kościelny, which lies approximately 14 kilometres (9 mi) east of Garwolin and 68 km (42 mi) south-east of Warsaw.

The gmina covers an area of 85.24 square kilometres (32.9 sq mi), and as of 2006 its total population is 5,019.

Gmina Miastków Kościelny contains the villages and settlements of Brzegi, Glinki, Kruszówka, Kujawy, Miastków Kościelny, Oziemkówka, Przykory, Ryczyska, Stary Miastków, Wola Miastkowska, Zabruzdy, Zabruzdy-Kolonia, Zasiadały, Zgórze, Zwola and Zwola Poduchowna.

Gmina Miastków Kościelny is bordered by the gminas of Borowie, Górzno, Stoczek Łukowski, Wola Mysłowska and Żelechów.

• Polish official population figures 2006

51°52′53″N 21°49′18″E / 51.88139°N 21.82167°E / 51.88139; 21.82167