| Avallersuaq | |
| Image Map Size: | 270px |
| Image Map Caption: | Map of Avallersuaq |
| Pushpin Map: | Greenland Southern Tip#Greenland |
| Pushpin Label: | Avallersuaq |
| Pushpin Map Caption: | Location of Avallersuaq in Greenland |
| Coordinates: | 59.8167°N -78°W |
| Location: | Irminger Sea Southern Greenland |
| Archipelago: | Nunap Isua Archipelago |
| Waterbody: | North Atlantic Ocean |
| Area Km2: | 4.30 |
| Length Km: | 5.2 |
| Width Km: | 2.0 |
| Coastline M: | --> |
| Elevation M: | 491 |
| Highest Mount: | Puto |
| Country: | Greenland |
| Country Admin Divisions Title: | Municipality |
| Country Admin Divisions: | Kujalleq |
| Country Area M2: | or |
| Country Area Ha: | --> |
| Population: | 0 |
| Population As Of: | 2023 |
| Density Km2: | 0 |
| Ethnic Groups: | none |
Avallersuaq, old spelling Avatdlerssuaq, is an uninhabited island of the Cape Farewell Archipelago in Kujalleq municipality of southern Greenland.
It is a small and rocky island located east of Itilleq Island (Egger). It has an elevation of . The small Saningassoq group of five islets lies to the north.[1]