Otisville is a village in Forest Township, Genesee County in the U.S. state of Michigan. The population was 864 at the 2010 census. It is located along M-15, just south of M-57.
The first land entry for the Forest (after the heavy growth of trees) community was made in March 1836 by James Seymour. The first settlers, Henry Heister and family, came in 1837. The township was organized in 1837, with the second settler, Nathaniel Smith, elected supervisor. In 1851, a sawmill was built by John Hayes, who sold the mill to Francis Otis the next year. On February 14, 1855, the post office opened with postmaster John Crawford. On April 5, 1861, the post office was renamed to Otisville. The village was platted by William F. Otis and T.D. Crocker in 1863.