| Sinceny | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason ville fr Sinceny (Aisne).svg |
| Arrondissement: | Laon |
| Canton: | Chauny |
| Insee: | 02719 |
| Postal Code: | 02300 |
| Mayor: | Bernard Pezet[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | CA Chauny Tergnier La Fère |
| Coordinates: | 49.5969°N 3.2472°W |
| Elevation M: | 70 |
| Elevation Min M: | 42 |
| Elevation Max M: | 113 |
| Area Km2: | 13.13 |
Sinceny (pronounced as /fr/) is a commune in the Aisne department in Hauts-de-France in northern France.