The former world number one was in ominous touch as she thrashed Japanese qualifier Naomi Osaka 6-1, 6-1 in 56 minutes on Rod Laver Arena to make it eight consecutive last-16 appearances at Melbourne Park.
It opens up a path to the quarter-finals for the Belarusian, with Spanish third seed Garbine Muguruza no longer a concern after she was shocked by Czech veteran Barbora Strycova in straight sets.
Azarenka, 27, has been in top early-season form, winning the Brisbane International and racing through her opening three matches in Melbourne for the loss of just five games.
After a torrid two years battling injuries, the 14th seed is back on a roll and is a clear threat to world number one and defending champion Serena Williams, who she could meet in the final.
“I’m pretty happy with the way I’m playing. I just want to still keep improving from match to match, because it’s only getting harder from here,” she said, revealing she hit the practice court immediately after the match.