Second-half goals from Senad Lulic and Danilo Cataldi won the match which was being played in Saudi Arabia for the second year running.
Lazio also beat Juventus 3-1 in Serie A on December 7, handing their opponents their first defeat under coach Maurizio Sarri.
Lazio, the Coppa Italia victors, went ahead after 17 minutes when Sergei Milinkovic-Savic laid the ball off for Luis Alberto to fire into the net.
Paulo Dybala levelled for the Serie A champions at the end of the first-half from a rebound after Cristiano Ronaldo's shot was parried by Thomas Strakosha.
Juventus seemed to be in control in the second half and Ronaldo was close with a shot which went just over but they were caught out when Marco Parolo's cross flew across the face of goal and Lulic volleyed in at the far post in the 73rd minute.
Juventus had midfielder Rodrigo Bentancur sent off in stoppage time and Cataldi curled the resulting free-kick into the net with the last action of the game.
The Super Cup final is often played abroad and has also been hosted in China, the United States, Libya and Qatar.