Chinese auto brands market share in China

In 2013 first half year:
Chinese own brands sold 3.56 million passenger cars. Roughly speaking, Chinese brands annual sale is about 7 million cars.

Chinese brands has a market share of the passenger cars of 41.2%.

SOURCE
根据中汽协发布的上半年产销数据:中国品牌乘用车销售356.67万辆,同比增长13.2%,占乘用车销售总量的41.2%,占有率比上年同期下降0.2个百分点。上半年分月情况看,有四个月占有率低于上年同期。数据表明,中国品牌乘用车市场份额降幅与上年相比有所收窄,但形势依然严峻,仍与外资品牌有一定的差距。