| Iberg Castle | |
| Native Name: | Yburg, Iburg |
| Built: | 1200 |
| Type: | hill castle |
| Condition: | Burg |
| Materials: | Rough cut bossage |
| Location: | Wattwil |
| Coordinates: | 47.2975°N 9.08°W |
| Map Type: | Canton of St. Gallen#Switzerland |
| Code: | CH-SG |
Iberg Castle (German: Burg Iberg) is a partly ruined castle in Wattwil in the canton of St. Gallen in Switzerland.