Grimacco (; ) is a (municipality) in the Regional decentralization entity of Udine in the Italian region Friuli-Venezia Giulia, located about northwest of Trieste and about northeast of Udine, on the border with Slovenia, and borders the following municipalities: Drenchia, Kanal ob SoÃÂi (Slovenia), Kobarid (Slovenia), San Leonardo, Savogna, Stregna.
Grimacco localities include Brida superiore (Gorenje Bardo), Brida inferiore (Dolenje Bardo), Canalaz (Kanalac), Clodig (HlodiÃÂ), Costne (Hostne), Dolina (Dolina), Grimacco Inferiore (Dolenji Garmak), Grimacco Superiore (Gorenji Garmak), Liessa (Liesa), Lombai (Lombaj), Plataz (Platac), Podlach (Podlak), Seuza (Selce), Slapovicco (Slapovik), Sverinaz (Zverinac), Topolò (Topolove), Ville di Mezzo. The municipal hall is located in Clodig.
, it had a population of 342 and an area of .
93.7% of the population were Slovenes according to the 1971 census.