| Semuy | |
| Commune Status: | Commune |
| Arrondissement: | Vouziers |
| Canton: | Attigny |
| Insee: | 08411 |
| Postal Code: | 08130 |
| Mayor: | Jean Frankart[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Crêtes Préardennaises |
| Coordinates: | 49.4883°N 4.6589°W |
| Elevation M: | 88 |
| Elevation Min M: | 82 |
| Elevation Max M: | 162 |
| Area Km2: | 3.97 |
Semuy is a commune in the Ardennes department in northern France.