| Isumrud Strait | |
| Location: |  Papua New Guinea, Madang Province |
| Coordinates: | -4.82°N 145.88°W |
| Islands: | Karkar Island |
| Pushpin Map: | Papua New Guinea |
| Pushpin Map Caption: | Isumrud Strait in PNG |
Isumrud Strait is the strait separating Karkar Island from mainland New Guinea in Madang Province, Papua New Guinea.[1] It's 500 km from Port Moresby.