| Corneillan | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason ville fr Corneillan (Gers).svg |
| Arrondissement: | Mirande |
| Canton: | Adour-Gersoise |
| Insee: | 32108 |
| Postal Code: | 32400 |
| Mayor: | Pascal Carreau[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Aire-sur-l'Adour |
| Coordinates: | 43.6572°N -0.1789°W |
| Elevation M: | 152 |
| Elevation Min M: | 85 |
| Elevation Max M: | 160 |
| Area Km2: | 8.47 |
Corneillan (in French pronounced as /kɔʁnɛjɑ̃/; Occitan (post 1500);: Cornelhan) is a commune in the Gers department in southwestern France.