Lake Omodeo (Italian: Lago Omodeo, Sardinian: Lagu Omodeu) is an artificial lake in central west Sardinia, Italy.

The dam, designed by the engineer Angelo Omodeo, was inaugurated in 1924, at that time it was the largest reservoir in Europe.

Today, Lake Omodeo is the largest artificial reservoir on Sardinia.

[1] A new dam was built in 1997, dedicated to the Sardinian medieval judge Eleonor of Arborea, it is 582 m long and 120 m wide.

A population of twait shad, relatively common in Italy but locally extinct elsewhere, has been established in the lake.