Hong Kong and mainland China shares opened lower on Wednesday following US losses as traders await a key tech earnings report and Fed policy meeting minutes later in the day.

The Hang Seng Index started down 0.5 percent at 16,172.

The Shanghai Composite Index was down 0.4 percent at 2,911, and the Shenzhen Composite Index on China's second exchange dropped 0.9 percent to 1,597. (AFP)