BYD Auto Co., Ltd. is a Chinese automobile manufacturer based in Xi'an, Shaanxi Province, and a wholly owned subsidiary of BYD Company. It was founded in 2003, following BYD Company's acquisition of Tsinchuan Automobile Company in 2002. Its principal activity is the design, development, manufacture and distribution of passenger cars and buses sold under the BYD brand. It also has a 50:50 joint venture with Daimler AG, Shenzhen BYD Daimler New Technology Co., Ltd., which develops and manufactures luxury electric cars sold under the Denza brand.
BYD Auto sold a total of 506,189 passenger cars in China in 2013, making it the tenth-largest selling brand and the largest selling Chinese brand. In 2015, BYD Auto was the best selling global electric vehicle brand, ahead of General Motors and Nissan. For a second year running, BYD was the world's top selling plug-in electric car manufacturer with over 100,000 units delivered in 2016, followed by Tesla Motors. In October 2016, BYD Auto became the all-time second largest global plug-in car manufacturer after the Renault-Nissan Alliance.