| Sugar Island 37A | |
| Official Name: | Sugar Island Indian Reserve No. 37A |
| Settlement Type: | Indian reserve |
| Pushpin Map: | Canada Southern Ontario |
| Pushpin Mapsize: | 200 |
| Coordinates: | 44.2167°N -86°W |
| Subdivision Type: | Country |
| Subdivision Type1: | Province |
| Subdivision Type2: | County |
| Subdivision Name2: | Peterborough |
| Subdivision Type3: | First Nation |
| Subdivision Name3: | Alderville |
| Area Land Km2: | 0.41 |
| Population As Of: | 2011 |
| Website: | www.alderville firstnation.ca |
Sugar Island 37A is an island and First Nations reserve within Rice Lake in southern Ontario. It is one of two reserves of the Alderville First Nation, along with Alderville.