World No.1 Sabalenka's streak includes winning titles at Wuhan in 2018, 2019 and 2024.
Sabalenka will next play eighth-seeded Elena Rybakina, who won 6-3 6-4 against Linda Noskova as she seeks to seal entry into the WTA Finals event in Saudi Arabia.
This will be a 13th meeting between them - with Sabalenka leading 7-5 - but Rybakina won their last match comfortably in Cincinnati in August.
Other big names also progressed on Thursday with Jessica Pegula, Iga Swiatek and Coco Gauff also booking their last-eight spots.
Pegula recovered from an early service break in the third set to beat Ekaterina Alexandrova 7-5 3-6 6-3.
Sixth-seeded Pegula, who lost in the China Open semi-finals last week, levelled the deciding set at 2-2, then won four of the last five games for victory.
The win over No.9 Alexandrova came a day after Pegula needed seven match points to beat fellow American Hailey Baptiste in the second round.
It was Pegula's sixth straight three-set match, and for the fifth time, she won.
"I can't remember the last time I played two sets," Pegula said. "But I've been competing really hard and I've been playing a lot of really good players.
"It was different conditions today with the roof closed and I think it took us a little while to get adjusted."
In the night matches, world No.2 Swiatek beat Swiss former Olympic champ Belinda Bencic 7-6 (7-2) 6-4.
Swiatek improved to a 5-1 career record over Bencic, including a straight-set win in the Wimbledon semi-finals in July.
In the quarters, the Pole will play Italian Jasmine Paolini, who advanced through the round of 16 when Denmark's Clara Tauson retired when trailing 3-6 6-1 3-1.
World No.3 Gauff, coming off a semi-final loss to eventual champion Amanda Anisimova at the China Open last week, defeated home player Zhang Shuai 6-3 6-2 and is set to face German Laura Siegemund in the quarters.
