John Harvey Baldwin (April 4, 1851 – June 19, 1924) was an American lawyer and politician.
Baldwin was born in Jonesborn, Grant County, Indiana and went to Spiceland Academy in Spiceland, Indiana.
In 1882, Baldwin moved to Hand County, Dakota Territory and continued to practice law.
He served as the South Dakota State Water Engineer for four years.
In 1900, Baldwin moved to Freeze, Becker County, Minnesota and continued to practice law.