Marty is a census-designated place in southern Charles Mix County, South Dakota, United States. The population was 677 at the 2020 census. The community has the name of Bishop Martin Marty, the Bishop of Sioux Falls, SD. The community is referred to as Ṡinasapa in Dakota language of the native Yankton Sioux Tribe. YST Transit buses connect the community to Wagner, Lake Andes and Ravinia.