Robert Horace Lounsberry (June 22, 1918 – February 10, 2001) was the Secretary of Agriculture for the state of Iowa from 1972 to 1987, a nationally known farmer advocate during the farming crises of the 1980s, and a powerful figure in the Republican Party at both the state and national level.

Shortly after graduating from Luther College in Decorah, Iowa, Lounsberry served in World War II as a U.S. Air Force B-24 pilot in the Asiatic Pacific Theater, where he received several military honors including the Distinguished Flying Cross, four Oak Leaf Clusters, and the Philippine Liberation Medal.

Lounsberry was active in the Republican Party, serving on the local, county, district and state levels.

He was a key player in the Iowa Presidential Caucus, with Presidents Ronald Reagan, George H. W. Bush, and George W. Bush all holding campaign events at his farm near McCallsburg, Iowa.

Lounsberry was appointed Iowa Secretary of Agriculture in 1972, and was re-elected in 1974, 1978, 1982 and served until retiring on January 3, 1987.