Middletown is a census-designated place (CDP) in Shiawassee County in the U.S. state of Michigan.

Middletown is located within Caledonia Township along M-71 between the cities of Corunna and Owosso.

As of the census[3] of 2000, there were 966 people, 374 households, and 264 families residing in the CDP.

There were 396 housing units at an average density of 808.9 per square mile (312.3/km2).

22.5% of all households were made up of individuals, and 8.0% had someone living alone who was 65 years of age or older.