Eiman (永万) was a Japanese era name (年号,, nengō,; lit. "year name") after Chōkan and before Nin'an. This period started in June 1165 and ended in August 1166. The reigning emperor was Emperor Rokujō-tennō (六条天皇).
| Eiman | 1st | 2nd |
| Gregorian | 1165 | 1166 |
| Preceded by: Chōkan |
Era or nengō: Eiman |
Succeeded by: Nin'an |