| Official Name: | Middlefield Township, Buchanan County |
| Settlement Type: | Township |
| Subdivision Type: | Country |
| Subdivision Type1: | State |
| Subdivision Type2: | County |
| Subdivision Name2: | Buchanan |
| Area Total Km2: | 90.56 |
| Area Land Km2: | 90.56 |
| Area Water Km2: | 0 |
| Unit Pref: | Imperial |
| Area Total Sq Mi: | 34.97 |
| Area Land Sq Mi: | 34.97 |
| Area Water Sq Mi: | 0 |
| Population As Of: | 2000 |
| Population Total: | 304 |
| Population Density Km2: | 3.4 |
| Population Density Sq Mi: | 8.7 |
| Elevation Footnotes: | [1] |
| Elevation M: | 302 |
| Elevation Ft: | 991 |
| Coordinates: | 42.4264°N -91.6531°W |
| Blank Name: | FIPS code |
| Blank Info: | 19-92919[2] |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 0468376 |
Middlefield Township is one of sixteen townships in Buchanan County, Iowa, United States. As of the 2000 census, its population was 304. Middlefield Township was established in 1858.[3]
Middlefield Township covers an area of 34.97sqmi and contains no incorporated settlements.