The second seeded Indian ace, who got the better of Belaetrix Manuputi of Indonesia in the previous round, won 23-21, 19-21, 21-16 in 74 minutes.
The Hyderabadi will meet the winner of another women's singles quarter-final between fourth seed Juliane Schenk of Germany and eighth seeded Thai Ratchanok Intanon on Saturday.
However, world No 9 Parupalli Kashyap's quest in the men's singles was cut short by second seed Chen Long, the Chinese winning 21-16, 21-10.
After saving a game point in the opening game and losing the second 19-21, world No 3 Saina came up with a brilliant display in the decider, engaging the Chinese in long rallies and scoring at the net whenever the opportunity arose.
After the scores ran neck and neck till 7-7, Saina reeled off seven straight points to establish a 13-7 lead and take command. The Chinese fought back but in vain as the Indian champion allowed her just a few points before clinching the issue on her second match point.
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