Buffalo Hart Township is located in Sangamon County, Illinois, USA. As of the 2010 census, its population was 173 and it contained 83 housing units. The township centers on the crossroads unincorporated community of Buffalo Hart and on the adjacent Buffalo Hart Grove, the remains of a historic grove of trees that once stood out amongst the tallgrass prairie of the pioneer township.
According to the 2010 census, the township has a total area of , all land.