| Plouguenast | |
| Native Name: | Plougonwaz |
| Image Coat Of Arms: | Blason de la ville de Plouguenast (Côtes-d'Armor).svg |
| Coordinates: | 48.2822°N -2.7031°W |
| Insee: | 22219 |
| Postal Code: | 22150 |
| Arrondissement: | Saint-Brieuc |
| Canton: | Guerlédan |
| Commune: | Plouguenast-Langast |
| Elevation Min M: | 112 |
| Elevation Max M: | 253 |
| Area Km2: | 35.12 |
| Population: | 1871 |
| Population Date: | 2019 |
| Population Footnotes: | [1] |
Plouguenast (pronounced as /fr/; br|Plougonwaz; Gallo: Ploegenas) is a former commune in the Côtes-d'Armor department of Brittany in northwestern France. On 1 January 2019, it was merged into the new commune Plouguenast-Langast.[2]
Plouguenast has an oceanic climate (Köppen climate classification Cfb). The average annual temperature in Plouguenast is . The average annual rainfall is with January as the wettest month. The temperatures are highest on average in August, at around, and lowest in January, at around . The highest temperature ever recorded in Plouguenast was on 9 August 2003; the coldest temperature ever recorded was on 2 January 1997.
Inhabitants of Plouguenast are called plouguenastais in French.