Hingis, a three-time singles champion at Melbourne Park, and Mirza dominated the first-set tiebreaker preceded by eight service breaks, four by each team.
The winners added to their Wimbledon and U.S. Open titles last year and the pair also won at Brisbane and Sydney this month. They started playing together at Indian Wells in March of last year.
Hingis is now a four-time doubles champion at the Australian Open. Mirza, who won the 2009 mixed doubles title with fellow Indian player Mahesh Bhupathi, was playing later Friday in mixed doubles semifinal with Ivan Dodig of Croatia.
Hlavackova and Hradecka are now 2-3 in Grand Slam doubles finals. They won major doubles titles at the 2011 French Open and 2013 U.S. Open.
Hingis's singles titles came in 1997, 1998 and 1999 when the tournament had only one stadium with a roof — Rod Laver Arena, where the doubles final was played Friday. It now has three.
"I feel like sometimes we struggle through the heat here in
Mirza said she'd have to rush off court to get ready for her mixed doubles semifinal.
"Thank you to my partner, we've had an incredible year, we just keep going and going," Mirza said. "She's an amazing champion, but I've gotten to know her as a person and it's a privilege to play with her."
Mirza and Dodig were to play Elena Vesnina and Bruno Soares in the mixed doubles semifinal. The winner of that match will play American Coco Vandeweghe and Horia Tecau of Romania in Sunday's final.
Soares is also in men's doubles final with Britain's Jamie Murray on Saturday. They'll play Daniel Nestor and Radek Stepanek.
(AP)