The Hang Seng Index lost 90 points, or 0.38 percent, to open at 23,620 points on Thursday.
Mainland stocks also opened lower, with the benchmark Shanghai Composite Index down 0.13 percent to open at 3,384 points.
The Shenzhen Component Index opened 0.19 percent lower at 10,156 points.
Overnight, the US Federal Reserve kept interest rates steady, leaving the federal funds rate in the 4.25 percent to 4.5 percent range, as policymakers continued to weigh the economic fallout from US President Donald Trump's expanding tariff regime. (Xinhua)