| Gahirmatha Marine Sanctuary | |
| Location: | Odisha, India |
| Nearest City: | Chandbali |
| Map: | India |
| Relief: | yes |
| Coordinates: | 20.57°N 86.84°W |
| Established: | 1997 |
Gahirmatha Marine Sanctuary is a marine wildlife sanctuary in the Indian state of Odisha, extending from the Dhamra River mouth in the north to Brahmani river mouth in the south.[1] It is the world's largest and most important nesting beach for olive ridley sea turtles.[2]