| Official Name: | Lost River Township |
| Settlement Type: | Township |
| Subdivision Type: | Country |
| Subdivision Type1: | State |
| Subdivision Type2: | County |
| Subdivision Name2: | Martin |
| Government Type: | Indiana township |
| Unit Pref: | Imperial |
| Area Total Sq Mi: | 42.75 |
| Area Land Sq Mi: | 42.29 |
| Area Water Sq Mi: | 0.46 |
| Area Water Percent: | 1.08 |
| Population As Of: | 2020 |
| Population Total: | 513 |
| Population Density Sq Mi: | auto |
| Elevation Footnotes: | [1] |
| Elevation M: | 172 |
| Elevation Ft: | 564 |
| Coordinates: | 38.5539°N -86.7642°W |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Postal Code Type: | ZIP codes |
| Postal Code: | 47432, 47527, 47581 |
| Area Code: | 812, 930 |
| Blank Name: | GNIS feature ID |
| Blank Info: | 453582 |
Lost River Township is one of six townships in Martin County, Indiana, United States. As of the 2020 census, its population was 513 and it contained 250 housing units.[2]
According to the 2010 census, the township has a total area of, of which (or 98.92%) is land and (or 1.08%) is water.[3]
(This list is based on USGS data and may include former settlements.)
The township contains these seven cemeteries: Anderson, Cornel, Emmons Ridge, Green, Jones, Simmons and Walker.