Rockport Colony is a small unincorporated community and census-designated place (CDP) in Hanson County, South Dakota, United States.

It is located on the James River, southwest of Alexandria and southeast of Mitchell, and is part of the Mitchell Micropolitan Statistical Area.

The population was 77 at the 2020 census.

[4] The elevation is 1,224 feet.

The Rockport Colony Elementary School, which had 24 students in 2008,[5][6] is not located in Rockport Colony, but is physically in the town of Alexandria.