Doberdò del Lago is a comune (municipality) in the Regional decentralization entity of Gorizia in the Italian region of Friuli-Venezia Giulia, located about 30 kilometres (19 mi) northwest of Trieste and about 11 kilometres (7 mi) southwest of Gorizia, and borders the following municipalities: Duino-Aurisina, Fogliano Redipuglia, Komen (Slovenia), Miren-Kostanjevica (Slovenia), Monfalcone, Ronchi dei Legionari, Sagrado and Savogna d'Isonzo. It is located in the westernmost part of the Karst Plateau.

Friuli-Venezia Giulia is one of the 20 regions of Italy and one of five autonomous regions with special statute. The regional capital is Trieste on the Gulf of Trieste, a bay of the Adriatic Sea.