SHANGHAI (Reuters) - General Motors Co (>> General Motors Company) said on Wednesday it aims to quadruple its share of China's luxury auto market to 10 percent by 2020 as the U.S. automaker launches new Cadillac models and expands its distribution network in the world's largest car market.

Bob Socia, head of GM's China operation, shared Cadillac's China growth target in a roundtable with reporters ahead of a ground-breaking ceremony for GM's new Cadillac plant on the outskirts of Shanghai.

"We are not only expanding in tier-one and tier-two cities, which would be pretty logical to Cadillac, but ... China's high-growth areas could be in tier-three or even four," he said.

GM, which sells brands including Buick and Chevrolet in China, has prioritized Cadillac sales in China as it battles for market share with other luxury brands such as BMW (>> Bayerische Motoren Werke AG), Mercedes (>> Daimler AG) and Audi (>> Volkswagen AG).

But the Cadillac's sharp styling with influences from U.S. stealth fighter aircraft has failed to ignite Chinese buyers' passions, according to analysts and Cadillac marketers' themselves.

GM sold 30,010 Cadillacs in China last year compared with 149,782 in the United States. It is targeting about 250,000 luxury car sales in China by the end of the decade.

GM has been toning down the look of Cadillac cars as part of an effort woo buyers in China, which CEO Dan Akerson told reporters would account for up to 40 percent of the world's total luxury auto market by the end of this decade.

With a refreshed version of the top-selling Cadillac SRX crossover and local production of the Cadillac XTS sedan this year, GM aims to triple Cadillac sales in China to 100,000 units within two years.

Cadillac's China sales jumped 74 percent year-on-year by volume in May, after nearly doubling during the previous month, making Cadillac the fastest-growing among GM's brands in the country.

China has become a crucial market for makers of luxury cars, with 2.7 million expected to be sold there each year by 2020, overtaking the United States as the world's leader in the segment.

GM plans to introduce more than 10 new or upgraded products in China on average each year through 2016. GM and its joint ventures sold a record 2.8 million vehicles in China in 2012, up 11.3 percent from a year earlier.

(Reporting by Samuel Shen and Norihiko Shirouzu; Editing by Jonathan Standing and Stephen Coates)