| Sand Island | |
| Map: | Washington |
| Location: | Grays Harbor |
| Coordinates: | 46.9617°N -124.0583°W |
| Country: | United States |
| Country Admin Divisions Title: | State |
| Country Admin Divisions: | Washington |
| Country Admin Divisions Title 1: | County |
| Country Admin Divisions 1: | Grays Harbor County |
Sand Island is an island in Grays Harbor, in the U.S. state of Washington. The entire island is occupied by Sand Island Natural Area Preserve, a protected area under the State Department of Natural Resources' Washington Natural Areas Program. The small sandy island is seasonally overtopped by the salt waters of the harbor.