Mirza and Bhupathi beat Nathalie Dechy of France and Andy Ram of Israel 6-3, 6-1 at Rod Laver Arena.
Bhupathi and Mark Knowles of the Bahamas lost the men's doubles final Saturday to American twins Bob and Mike Bryan.
Seven of the 34-year-old Bhupathi's majors have come in mixed doubles. He won a mixed title at the Australian Open in 2006 with Martina Hingis.
Bhupathi and 22-year-old Mirza broke Dechy's serve in the opening set, then broke their opponents twice in the second. Bhupathi was dominant at the net throughout the match.
Player Ratings: Catania 0-2 Inter
Mirza, Bhupathi win mixed doubles title
Mirza, Bhupathi win mixed doubles title
