Popłacin [pɔˈpwat͡ɕin] is a village in the administrative district of Gmina Nowy Duninów, within Płock County, Masovian Voivodeship, in east-central Poland. It lies approximately 12 kilometres (7 mi) east of Nowy Duninów, 5 km (3 mi) west of Płock, and 100 km (62 mi) west of Warsaw.