Ng, who first appeared in the prestigious competition in 2016, was beaten in the round of 16 by France’s rising star Alex Lanier 17-21, 12-21 in 45 minutes.
The pair had split their four previous meetings, the last of which came in 2024 when Ng beat Lanier at the China Masters round of 16.
Ng, who’s number 30 in the world, lost the opening game after unsuccessfully challenging a long shot which went out of bounds.
Lanier, ranked 16th, dictated the pace the rest of the way, cruising to victory.
With the latest defeat, Ng, who turned 32 in June, has been eliminated in the last 16 of the World Championships seven times.
The women’s doubles pair of Lianne Yeung and Yeung Pui-lam are the only remaining Hong Kong, China players in the tournament.
The 20th-ranked SAR pair took out Hsu Yin-hui and Lin Jhih-yun of Chinese Taipei 21-18, 21-16 to reach the quarter-finals for the first time.
