There are 4 mathematicians whose last name begin with SIEN.
| Sien, Que Giok | Rijksuniversiteit Groningen | 1954 |
| Siene, James | Lehigh University | 2023 |
| Sienkiewicz, Łukasz | Uniwersytet Warszawski | 2021 |
| Sienra Loera, Guillermo Javier Francisco | University of Southampton | 1980 |