| Piaçabuçu | |
| Official Name: | The Municipality of Piaçabuçu |
| Nickname: | PBU |
| Subdivision Type: | Country |
| Subdivision Type1: | Region |
| Subdivision Type2: | State |
| Subdivision Name: |  Brazil |
| Subdivision Name1: | Northeast |
| Subdivision Name2: | Alagoas |
| Leader Title: | Mayor |
| Leader Name: | Dalmo Moreira Santana Júnior (PSB) |
| Established Title: | Founded |
| Established Date: | May 31, 1832 |
| Area Total Km2: | 242.9 |
| Population As Of: | 2020 |
| Population Note: | [1] |
| Population Total: | 17,848 |
| Population Density Km2: | 82.0 |
| Timezone: | BRT |
| Utc Offset: | -3 |
| Coordinates: | -10.4058°N -36.4339°W |
| Elevation M: | 5 |
| Blank Name: | HDI (2000) |
| Blank Info: | 0.613 – medium[2] |
Piaçabuçu is a municipality located in the Brazilian state of Alagoas. It is the southernmost municipality in Alagoas, and lies near both São Francisco River and the Atlantic Ocean. Its population was 17,848 (2020) and its area is 240 km2.[3]