Rosemary E. LaPlanche (October 11, 1923 – May 6, 1979) was Miss America in 1941.
Rosemary LaPlanche moved to southern California from Kansas with her mother and sister, Louise LaPlanche, at a very early age. LaPlanche, who lived in Los Angeles, California, was Miss California in both 1940 and 1941. A new rule after her victory disallowed contestants from competing at the national level more than once. She also had an active career as a movie actress. She was married to Harry Koplan from 1947 until his death in 1973, and had two children: a daughter Carol and son Terry.