| Guignen | |
| Native Name: | (Gallo) |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason ville fr Guignen (Ille-et-Vilaine).svg |
| Coordinates: | 47.9211°N -1.8606°W |
| Insee: | 35127 |
| Postal Code: | 35580 |
| Arrondissement: | Redon |
| Canton: | Guichen |
| Mayor: | Evelyne Lefeuvre[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Vallons de Haute-Bretagne |
| Elevation Min M: | 21 |
| Elevation Max M: | 122 |
| Area Km2: | 53.05 |
Guignen (in French pronounced as /ɡiɲɛ̃/; ; Gallo: Ginyen) is a commune in the Ille-et-Vilaine department in Brittany in northwestern France.
The title of Viscount of Guignen had been the property of the House of Rohan since the 15th century. It was passed through to the Princes of Condé, members of the House of Bourbon by a marriage between Louis Joseph de Bourbon, Prince of Condé to Charlotte de Rohan who was created Viscountess in 1745. At her death in 1760, it became one of the subsidiary titles of the Condé's being confiscated during the revolution.
Inhabitants of Guignen are called Guignennais in French.