Appointed on a two-year deal in June last year, Chivu delivered a domestic double in his debut season, winning both Serie A and the Coppa Italia.
The 45-year-old Romanian, who spent seven years at Inter as a defender, was also named Serie A coach of the season.
"Triumphs and spectacular achievements, possible only for those who truly know what it means to have passion for Inter, a value that has defined the entire season and will once again guide Cristian Chivu until 2028," Inter said in a statement.