James A. Lantz (September 15, 1921 – June 19, 2014) was an American lawyer and politician.
Born in Fairfield County, Ohio, Lantz served in the United States Army Air Forces as a pilot.
From 1953 to 1963, Lantz served as a Democrat in the Ohio House of Representatives and was speaker in 1959.
Lantz lost the Democratic primary election for Lieutenant Governor of Ohio.
He returned to his law practice in Lancaster, Ohio, and was involved in the insurance business.