The World number two Indian took just 26 minutes to get the better off Ponsana 21-10 21-12 in the second round of the women's singles event.
However, Commonwealth Games bronze medallist P Kashyap had a disappointing day on the court as the Indian lost in straight-games to fifth seed Jin Chen of China.
Kashyap was defeated 15-21-18-21 by Chen in a 45 minute battle in men's singles.
Saina surged ahead from 4-4 to a eight point lead and then extended the lead to 16-5 and 18-10 before pocketing the first game comfortably.
The second game was no different as she opened a five point lead at 6-1 and then held her fort to complete a convincing victory.
Saina had played Ponsana twice before -- the Hong Kong Super Series in 2008 and the Thomas and Uber Cup -- and the Indian has a 100 per cent record against her Thai rival.
The 20-year-old will take on the winner of the match between Pui Yin Yip and seventh seed Korean Youn Joo Bae in the quarterfinals on Friday.