Kawainui Marsh
| Kawainui Fishpond (Marsh) | |
|---|---|
| Kawainui Fishpond | |
| Location | Kailua, Hawaii |
| Coordinates | 21°23′31″N 157°45′29″W / 21.391864°N 157.758028°W |
| Type | Wetland |
| Official name | Kawainui and Hamakua Marsh Complex |
| Designated | 2 February 2005 |
| Reference no. | 1460 |
Kawainui Fishpond or Kawainui Marsh is a wetland and resurfacing fishpond in Kailua, Hawaiʻi. It is the largest remaining wetland and the largest ancient freshwater fishpond in Hawaiʻi, and a designated Ramsar Convention wetland.