In the first nine months of the year, GM and its joint ventures sold a record 1.89 million vehicles in the world's biggest auto market, up 6.6 percent year on year, the company said in a statement.
"GM has maintained our momentum in China, with all of our major brands setting new September sales marks," said GM China Group president Kevin Wale.
GM said its September sales -- the second-highest for a single month -- puts the auto maker on track to surpass two million units for the 10 months ending October and set a record for the entire year.
China has been phasing out incentives such as tax breaks for small engine vehicles, originally implemented to ward off the impact of the global financial crisis.
Total sales in China are expected to grow five percent in 2011, lower than an earlier forecast of 10-15 percent and less than the 32 percent increase last year, according to the China Association of Automobile Manufacturers.
For the January-August period, China's vehicle sales rose 3.3 percent to 11.98 million vehicles.