The Lower Peninsula of Michigan is the southern of the two major landmasses of the U.S. state of Michigan. It is surrounded by water on all sides except its southern border, which it shares with Ohio and Indiana. Geographically, the Lower Peninsula has a recognizable shape that many people associate with a mitten, with the mid-eastern region identified as The Thumb. This has led to several folkloric creation myths for the area, one being that it is a hand print of Paul Bunyan, a giant lumberjack and favorite European-American folk character in Michigan. When asked where they live, Lower Peninsula residents may hold out a hand and point to a spot on it to indicate the location. The peninsula is sometimes divided into the Northern Lower Peninsula and Southern Lower Peninsula.

The Lower Peninsula has been nicknamed "The Mitten", "Below the Bridge", and occasionally "The L.P." (in parallel with "the U.P." for the Upper Peninsula). Residents of the Lower Peninsula are jokingly referred to as "flat-landers," or "trolls" by residents of the Upper Peninsula, because they live "under the bridge".