Tesla's China-made electric vehicle sales grew 3% in August from a year earlier, while deliveries of its China-made Model 3 and Model Y vehicles rose 17% from July.
Chinese rival BYD reported a 35.3% year-on-year jump in passenger vehicle sales in August, and other local EV competitors also saw higher sales.
Tesla's rising China numbers, including domestic sales and exports, were aided by extended incentives for local buyers and government backing.
Tesla has been offering a financing plan with a zero-interest loan to attract buyers, and has won endorsement from several local governments for official car purchases.