The benchmark Hang Seng Index eased 0.12 percent, or 23.29 points, to 19,788.51 on turnover of HK$43.74 billion ($5.64 billion).
Traders have been expecting policymakers to ease monetary policy -- either by cutting interest rates or the amount of cash banks must keep in reserve -- in order to kickstart the slowing economy.
However, the lack of action has led to selling pressure.
"Economic difficulties persist, while the anticipated reserve requirement cut has yet to materialise," Zheshang Securities analyst Zhang Yanbing told AFP.
Bernanke's speech at an annual meeting of central bankers at Jackson Hole, Wyoming, on Friday is in focus as investors look for any plans the Fed has to stimulate the stuttering US economy.
"Fundamentally, there are no reasons to chase stocks higher," said Alvin Cheung, an associate director at Prudential Brokerage. But at the same time, investors did not dare "aggressively sell down stocks, on fears of a US Fed easing-induced rally. Hence, we're stuck here," he told Dow Jones Newswires. Insurer China Life rose 2.0 percent to HK$20.70 despite a 26-percent drop in its first-half net profit. Investors were cheered by the 2.5 percent rise in new business value. Want Want China fell 4.5 percent to HK$9.68, despite the snacks and beverages maker reporting a 38-percent rise in first-half net profit and Casino operator Galaxy Entertainment ended 3.4 percent higher at HK$22.65. Chinese shares ended down 0.96 percent, near a three-and-a-half-year low.
The benchmark Shanghai Composite Index closed down 19.91 points to 2,053.24 on turnover of 41.6 billion yuan ($6.6 billion).
The index is at its lowest level since February 2, 2009.
Rare earth stocks fell on declining exports. Rising Nonferrous Metals slumped 7.50 percent to 47.97 yuan while Baotou Steel Rare-Earth fell 6.64 percent to 32.91 yuan.
Blue-chip companies fell on profit-taking after gains the previous session.
Oil giant Sinopec dropped 3.05 percent to 6.04 yuan and PetroChina fell 1.56 percent to 8.81 yuan. Baoshan Iron and Steel, which announced a share buy-back this week, lost 2.68 percent to 4.36 yuan.
