The Kansas City Mule and St. Louis Mule were a pair of 283-mile (455 km) passenger trains operated by Amtrak running between St. Louis and Kansas City, Missouri as part of the Missouri Service train network.

[1] Amtrak introduced the two trains on October 26, 1980, in partnership with the state of Missouri, which provided a yearly subsidy of $484,000.

Contemporary news accounts referred to the combined service as the "Missouri Mule", although Amtrak timetables used the individual names.

Amtrak added Lee's Summit and Washington as flag stops in April 1981 on a one-year trial basis; Lee's Summit was retained in 1982 while Washington was dropped late 1981 in favor of Independence.

This often resulted in severe delays for Amtrak, such as those seen in May 2007, when the Missouri Department of Transportation blamed UP for the disruptions.