Spézet (French pronunciation: [spezɛt]; Breton: Speied) is a commune in the Finistère department of Brittany in north-western France.

It is bounded on the west and north by the river the Aulne and Hyères describing large meanders (Nantes-Brest Canal-channel) while at the southeast end of its territory lies Roc'h Toullaëron, which from its height of 318 m is the culmination of the Black Mountains.

Spézet is border by Saint-Hernin to the east, by Gourin to the southeast, by Roudouallec to the south, by Saint-Goazec to the southwest, by Châteauneuf-du-Faou to the west and by Plonévez-du-Faou, Landeleau and Cleden-Poher to the north.

During the Revolt of the Bonnets Rouges ("Red Caps") in 1675, the parishioners involved in the ransacking of the Kergoet castle in Saint-Hernin, owned by the Marquis Le Moyne de Trevigny.

June 24, 1944, ten resistants arrested in Spézet were shot in Lanvénégen after being sentenced to death by the German military court sitting in Le Faouët.