| Little Island | |
| Image Alt: | Aerial image of an island. |
| Pushpin Map: | United States San Francisco Bay Area#USA California#USA |
| Coordinates: | 38.18°N -122.3514°W |
| Location: | Northern California |
| Waterbody: | Napa River |
| Area Sqft: | or |
| Area Acre: | --> |
| Length Ft: | --> |
| Width Ft: | --> |
| Coastline Ft: | --> |
| Elevation Ft: | 3 |
| Country: | United States |
| Country Admin Divisions Title: | State |
| Country Admin Divisions Title 1: | County |
| Country Admin Divisions 1: | Napa and Solano |
Little Island is a partially submerged marsh island in the Napa Slough, branching off from the Napa River upstream of San Pablo Bay (an embayment of San Francisco Bay). It is almost entirely in Napa County, California, although part of its southern tip is in Solano County; it is managed as part of the Napa-Sonoma Marshes Wildlife Area. Its coordinates are 38.18°N -122.3514°W, and the United States Geological Survey measured its elevation as in 1981.