Gmina Ustronie Morskie is a rural gmina (administrative district) in Kołobrzeg County, West Pomeranian Voivodeship, in north-western Poland. Its seat is the village of Ustronie Morskie, which lies approximately 14 kilometres (9 mi) north-east of Kołobrzeg and 118 km (73 mi) north-east of the regional capital Szczecin.
The gmina covers an area of 57.27 square kilometres (22.1 sq mi), and as of 2006 its total population is 3,613.
Gmina Ustronie Morskie contains the villages and settlements of Bagicz, Grąbnica, Gwizd, Jaromierzyce, Kukinia, Kukinka, Malechowo, Olszyna, Rusowo, Sianożęty, Ustronie Morskie and Wieniotowo.
Gmina Ustronie Morskie is bordered by the gminas of Będzino, Dygowo and Kołobrzeg.