Defending champion Ding Ning of China beat Park Seonghye of South Korea in straight sets to reach the women's singles quarterfinals of at the World Championships here on Friday.

The top seed eased past the 166th-ranked Park 11-8, 11-4, 11-5, 11-7 for the win.

Ding, beaten finalist in last year's London Olympic Games, will next take on Ri Myong Sun of DPR Korea, who defeated Austria's Liu Jia in the other match.

Chinese women booked five out of eight berths in the quarterfinals and the day's only loser from the Chinese team is Cheng Men, who was beaten by Olympic champion and teammte Li Xiaoxia.

Li, the world No.3, beat Cheng 11-6, 11-6, 11-3, 11-9.

Li will next meet another Chinese Wu Yang, an 11-2, 11-9, 11-4, 11-7 winner over Kim Hye Song of DPR Korea.

World No.2 Liu Shiwen eliminated Seo Hyowon of South Korea and Zhu Yuling beat Jiang Huajun of Hong Kong, China.