The fresh models include the all-new Encore small SUV and Encore GX compact SUV, said GM.
The Encore, Buick's first SUV built in China, originally went on sale in 2012. The long-wheelbase Encore GX is a new addition to the family, positioned between the smaller Encore and the larger Envision.
Buick has planned to introduce eight new and refreshed products in 2019 and more than 20 new and refreshed models by 2023 in China, now the world's biggest auto market.
The introduction of new vehicles "will give Buick a strong presence across small, compact, midsize and large SUVs in its largest market - strengthening the brand's overall competitiveness in one of the most competitive segments," said Molly Peck, executive director of Buick for SAIC-GM, a Shanghai-based joint venture.
The U.S. automaker reported a 12.2 percent year-on-year decline in the second quarter sales in China.
However, GM said its brands continued to progress and expand their presence in China even in a weak quarter, with the high-end brand Cadillac delivering 66,523 units, seeing a 36.6 percent year-on-year rise. But Buick suffered a 14.1 percent decline in sales.
GM said that it has been carrying out a "significant product changeover" in China, with a sharpened focus on luxury vehicles and SUVs.
Car sales in China remained sluggish in the first half of this year after a weak performance in 2018, registering a 12.4-percent drop year on year, according to data from China Association of Automobile Manufacturers.
Yet China's car sales rebounded in June as automakers and dealers ratcheted up promotion before new emission standards went into force in some regions in July.
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