| Rio Largo | |
| Settlement Type: | Municipality of Alagoas, Brazil |
| Image Alt: | Lourenço de Albuquerque train station |
| Flag Alt: | Flag of Rio Largo |
| Map Alt: | Location of Rio Largo in Alagoas |
| Pushpin Map: | Brazil#South America |
| Pushpin Relief: | yes |
| Coordinates: | -9.4778°N -35.8528°W |
| Subdivision Type: | Country |
| Subdivision Name: |  Brazil |
| Subdivision Type1: | Region |
| Subdivision Type2: | State |
| Subdivision Name1: | Northeast |
| Established Title: | Founded |
| Established Date: | 31 March 1938[1] |
| Leader Title1: | Mayor |
| Leader Name1: | Gilberto Gonçalves da Silva (PP) (2021-2024)[2] |
| Leader Title2: | Vice Mayor |
| Leader Name2: | Maria Cristina Cordeiro da Silva (PP) (2021-2024) |
| Area Total Km2: | 293.816 |
| Elevation M: | 130 |
| Population As Of: | 2022 |
| Population Total: | 93927[3] |
| Population Density Km2: | 319.68 |
| Population Demonym: | Rio-larguense (Brazilian Portuguese) |
| Timezone: | Brasília Time |
| Utc Offset: | -03:00 |
| Postal Code Type: | Postal code |
| Postal Code: | 57100-000, 57110-000[4] |
| Blank Name: | HDI (2010) |
| Blank Info: | 0.643 – medium |
| Website: | riolargo.al.gov.br |
Rio Largo is a municipality located in the Brazilian state of Alagoas. Its population was 75,394 (2020)[5] and its area is 309 km².[6]