William "Bill" McKenna (born August 29, 1946) is a former American Democratic politician who served in the Missouri Senate and the Missouri House of Representatives from 1983 to 1993. Born in St. Louis, Missouri, McKenna graduated from St. Louis University High School and Southeast Missouri State University with a bachelor's degree in education. He served in the U.S. Army Reserves from 1968 until 1974.His son Ryan McKenna has also served in the Missouri Senate and the Missouri House of Representatives while his father J. Glennon McKenna served in the Missouri House of Representatives in the 1940s. He is also related to T. J. McKenna who has served in the Missouri House of Representatives.