The pace of growth was faster than the 1.7 percent year-on-year rise achieved in September.
For the first ten months, sales were up 11 percent to 2.3 million units, the company said in a statement.
GM makes vehicles in China in partnership with FAW Group and SAIC Motor Corp.
Its flagship car venture in Shanghai sold 117,611 cars in October, up 14 percent from a year earlier. Sales of its mini van venture in south China came to 129,806, up 16 percent.