Dolegna del Collio (; Standard Friulian: ; Southeastern Friulian: ) is a (municipality) in the Regional decentralization entity of Gorizia in the Italian region of Friuli-Venezia Giulia, located about northwest of Trieste and about northwest of Gorizia, on the border with Slovenia. , it had a population of 419 and an area of .
The municipality of Dolegna del Collio contains the (boroughs) Mernicco, Restoccina, Ruttars, Scriò, Trussio, Breg, Lonzano, Venco, and Barbana nel Collio.
Dolegna del Collio borders the following municipalities: Brda (Slovenia), Cormons, Corno di Rosazzo, Prepotto.