| Official Name: | Masiaboay |
| Pushpin Map: | Madagascar |
| Pushpin Label Position: | bottom |
| Pushpin Map Caption: | Location in Madagascar |
| Pushpin Mapsize: | 180 |
| Subdivision Type: | Country |
| Subdivision Type1: | Region |
| Subdivision Name1: | Atsimo-Andrefana |
| Subdivision Type2: | District |
| Subdivision Name2: | Betioky Sud |
| Population As Of: | 2001 |
| Population Total: | 10000 |
| Population Blank1 Title: | Ethnicities |
| Population Blank2 Title: | Religions |
| Timezone: | EAT |
| Utc Offset: | 3 |
| Coordinates: | -23.9°N 72°W |
| Elevation Footnotes: | [1] |
| Elevation M: | 245 |
Masiaboay is a town and commune (Malagasy: kaominina) in southwest Madagascar. It belongs to the district of Betioky Sud, which is a part of Atsimo-Andrefana Region. The population of the commune was estimated to be approximately 10,000 in 2001 commune census.
Only primary schooling is available. The majority 60% of the population of the commune are farmers, while an additional 39% receives their livelihood from raising livestock. The most important crops are cassava and maize, while other important agricultural products are peanuts and sweet potatoes. Services provide employment for 1% of the population.[2]