The Shanghai Stock Exchange was down 0.9 percent by lunchtime, while Shenzhen had fallen as much as 2.6 percent.
South Korea's Kospi fell 2.1 percent, despite earlier reports that Samsung Electronics' operating profit had surged more than 780 percent in the third quarter compared with the same period last year.
Japan's Topix was also down, by 0.3 percent, while the Nikkei 225 went against the trend, rising 0.4 percent.
The Hong Kong-based Hang Seng rose 0.1 percent.
