| Unit Pref: | Imperial |
| Settlement Type: | Township |
| Official Name: | Grand Detour Township |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Illinois |
| Subdivision Type2: | County |
| Subdivision Name2: | Ogle |
| Leader Title: | Supervisor |
| Leader Name: | Francis Drew, Jr |
| Area Total Sq Mi: | 11.49 |
| Area Land Sq Mi: | 10.91 |
| Area Water Sq Mi: | 0.58 |
| Area Water Percent: | 5.05 |
| Population As Of: | 2010 |
| Population Density Sq Mi: | 64 |
| Timezone: | CST |
| Utc Offset: | -6 |
| Timezone Dst: | CDT |
| Utc Offset Dst: | -5 |
| Pop Est As Of: | 2016 |
| Pop Est Footnotes: | [1] |
| Population Est: | 671 |
| Blank Name: | FIPS code |
| Blank Info: | 17-141-30718 |
Grand Detour Township is located in Ogle County, Illinois. As of the 2010 census, its population was 698 and it contained 385 housing units.[2]
According to the 2010 census, the township has a total area of, of which (or 94.95%) is land and (or 5.05%) is water.[2] The township's land use is predominantly agriculture with single-family residential uses in the southeastern portion of the township.[3]
It is located in a multi-township assessment district with Pine Creek, Eagle Point, and Woosung townships.[4] The township is coterminous with the township's sole voting precinct.[5]