La Plant is a census-designated place (CDP) in Dewey County, South Dakota, United States.

La Plant was laid out in 1910, and named in honor of a local cattleman.

[6] La Plant is located in east-central Dewey County and U.S. Route 212 passes through the community, leading west 32 miles (51 km) to Eagle Butte and east 39 miles (63 km) to Gettysburg.

11.8% of all households were made up of individuals, and 5.9% had someone living alone who was 65 years of age or older.

There were 62.5% of families and 61.6% of the population living below the poverty line, including 48.5% of those under 18 and 56.3% of those over 64.