Hinton St Mary is a village and civil parish in the county of Dorset in southern England. It is sited on a low Corallian limestone ridge beside the River Stour, 1 mile (1.6 km) north of the market town Sturminster Newton. It lies within the North Dorset administrative district. In 2001 the parish had 97 households and a population of 221. In 2013 the estimated population of the parish was 260.