China Unicom, the country's second largest telecom operator duelly listed in China and the U.S. (Ticker: CHU), said Saturday its net profit might have dropped by more than 50 percent in 2009, as the one-time gain from the sale of a mobile business laid a higher comparison basis for 2008.

China Unicom, in October 2008, sold its Code Division Multiple Access (CDMA) business and related assets to China Telecom, the largest fixed line service provider of the country, which substantially increased the profits of the company in 2008.

The company said in a statement filed to the Shanghai Stock Exchange that its profit was also affected by the high costs for its new Wideband-CDMA operations.