| Coulmier-le-Sec | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason de la ville de Coulmier-le-Sec (21).svg |
| Arrondissement: | Montbard |
| Canton: | Châtillon-sur-Seine |
| Insee: | 21201 |
| Postal Code: | 21400 |
| Mayor: | Lydie Martin[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Pays Châtillonnais |
| Coordinates: | 47.7508°N 4.4936°W |
| Elevation M: | 334 |
| Elevation Min M: | 258 |
| Elevation Max M: | 371 |
| Area Km2: | 32.29 |
Coulmier-le-Sec (in French pronounced as /kulmje lə sɛk/) is a commune in the Côte-d'Or department in eastern France.