Weidman is an unincorporated community in Isabella County in the U.S. state of Michigan. It is a census-designated place (CDP) for statistical purposes, but had no independent municipal authority. The population of the CDP was 879 at the 2000 census.The community is situated on the boundary between Nottawa Township on the east and Sherman Township on the west. The area of the CDP within Sherman Township is somewhat larger than that within Nottawa Township.