| Official Name: | Atsimo Andrefana Region |
| Native Name: | Région Atsimo Andrefana |
| Settlement Type: | Region |
| Mapsize: | 180px |
| Subdivision Type: | Country |
| Seat Type: | Capital |
| Seat: | Toliara |
| Leader Title: | Governor |
| Leader Name: | Edally Tovondrainy Ranoelson |
| Area Total Km2: | 66236 |
| Population As Of: | 2018 |
| Population Footnotes: | [1] |
| Population Total: | 1799088 |
| Population Density Km2: | auto |
| Population Blank1 Title: | Ethnicities |
| Population Blank2 Title: | Religions |
| Timezone: | EAT |
| Utc Offset: | 3 |
| Blank Name Sec1: | HDI (2018) |
| Blank Info Sec1: | 0.418[2] · 21st of 22 |
Atsimo-Andrefana (South West) is a region of Madagascar. It borders Menabe in north, Amoron'i Mania and Haute Matsiatra in northeast, Ihorombe and Anosy in east and Androy in southeast. The capital is Toliara and the population was 1,799,088 in 2018.[3] Atsimo Andrefana is geographically the largest of all Malagasy regions with an area of 662360NaN0.[4]
Atsimo-Andrefana Region is divided into nine districts, which are sub-divided into 105 communes.
In Atsimo-Andrefana are found the following protected areas:
Mayor river in Atsimo-Andrefana is the Onilahy River and in the north the Mangoky River.Also the Fiherenana River and Linta River flows in that region while the Menarandra River forms the border with region of Androy in the south.