| Official Name: | Lemannville, Louisiana |
| Settlement Type: | Census-designated place |
| Pushpin Map: | Louisiana |
| Pushpin Label: | Lemannville |
| Pushpin Map Caption: | Location within the state of Louisiana |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Louisiana |
| Subdivision Type2: | Parishes |
| Subdivision Name2: | Ascension, St. James |
| Unit Pref: | Imperial |
| Area Footnotes: | [1] |
| Area Total Km2: | 3.30 |
| Area Land Km2: | 2.62 |
| Area Water Km2: | 0.68 |
| Area Total Sq Mi: | 1.27 |
| Area Land Sq Mi: | 1.01 |
| Area Water Sq Mi: | 0.26 |
| Population As Of: | 2020 |
| Population Total: | 695 |
| Population Density Km2: | 264.98 |
| Population Density Sq Mi: | 686.08 |
| Timezone: | Central (CST) |
| Utc Offset: | -6 |
| Timezone Dst: | CST |
| Utc Offset Dst: | -5 |
| Elevation Ft: | 21 |
| Coordinates: | 30.1092°N -90.9203°W |
| Postal Code Type: | ZIP code |
| Blank Name: | FIPS code |
| Blank Info: | 22-43255 |
Lemannville is an unincorporated community and census-designated place in Ascension and St. James parishes, Louisiana, United States. It was first listed as a CDP in the 2010 Census. Per the 2020 census, the population was 695.[2]
Lemannville is located on the west bank of the Mississippi River along Louisiana Highway 18, 6miles east of Donaldsonville and 60miles west of New Orleans.
| White alone (NH) | 250 | style='background: #ffffe6; | 135 | 29.07% | style='background: #ffffe6; | 19.42% | |
| Black or African American alone (NH) | 599 | style='background: #ffffe6; | 533 | 69.65% | style='background: #ffffe6; | 76.69% | |
| Native American or Alaska Native alone (NH) | 0 | style='background: #ffffe6; | 1 | 0.00% | style='background: #ffffe6; | 0.14% | |
| Asian alone (NH) | 0 | style='background: #ffffe6; | 0 | 0.00% | style='background: #ffffe6; | 0.00% | |
| Pacific Islander alone (NH) | 0 | style='background: #ffffe6; | 0 | 0.00% | style='background: #ffffe6; | 0.00% | |
| Other race alone (NH) | 0 | style='background: #ffffe6; | 0 | 0.00% | style='background: #ffffe6; | 0.00% | |
| Mixed race or Multiracial (NH) | 2 | style='background: #ffffe6; | 8 | 0.23% | style='background: #ffffe6; | 1.15% | |
| Hispanic or Latino (any race) | 9 | style='background: #ffffe6; | 18 | 1.05% | style='background: #ffffe6; | 2.59% | |
| Total | 860 | style='background: #ffffe6; | 695 | 100.00% | style='background: #ffffe6; | 100.00% |