Greenfield Township is one of the sixteen townships of Warren County, Iowa, United States. Its estimated population as of 2008 is 5,773 people, with a density of . Three cities have land in Greenfield (Norwalk, Spring Hill, and Des MoinesâÂÂthe state capital), as well as two unincorporated areas (Greenbush and Scotch Ridge). The township has two cemeteries (Webb Cemetery and North Ridge).
At an elevation of , Greenfield Township covers an area of . The North River, a tributary of the Des Moines River, passes through Greenfield Township.