Gennin (元仁) was a Japanese era name (年号,, nengō,; lit. "year name") after Jōō and before Karoku. This period spanned the years from November 1224 to April 1225. The reigning emperor was Go-Horikawa-tennō (後堀河天皇).
| Gennin | 1st | 2nd |
|---|---|---|
| 1224 | 1225 |
| Preceded by: Jōō |
Era or nengō: Gennin |
Succeeded by: Karoku |