The Hang Seng Index gained 0.4 per cent to 25,522.09 as of 10.08am local time. The Hang Seng Tech Index added 0.3 per cent.
On the mainland, the CSI 300 Index climbed 0.3 per cent and the Shanghai Composite Index added 0.4 per cent.
China Telecom added 0.4 per cent to HK$5.72 and JD Logistics advanced 1.8 per cent to HK$13.33 as the companies were added to the Hang Seng Index for the first time. Another newcomer, Pop Mart International, tumbled 6.7 per cent to HK$288.40. Alibaba Group Holding rallied 3.9 per cent to HK$136.90 and Tencent Holdings added 1.3 per cent to HK$613.50.
A resumption of the gains in mainland stocks instilled confidence in Hong Kong equities. Hong Kong stocks have been taking cues recently from China’s onshore markets, which have been on a roll after a rotation out of fixed-income products.
Investors are closely watching China’s August economic data due this week for clues on whether the bull run can be sustained. Figures on foreign trade will be disclosed on Monday.