Sheets of Mongolia, 1980 incomplete
| Issuer | Date | Desc | State | ||
| - |  |
Mongolia | 5/5/1980 | sheet of 1 type | incomplete |
| - |  |
Mongolia | 6/2/1980 | Olympics 1980, sheet of 1 type | incomplete |
| - |  |
Mongolia | 9/15/1980 | empty sheet (#16832) | incomplete |
| - |  |
Mongolia | 12/29/1980 | IYC, empty sheet (#16838) | incomplete |