E-commerce China Dangdang Inc. (Chinese: 当当网), known as Dangdang, is a Chinese electronic commerce company, founded by Peggy Yu and Li Guoqing in 1999. It is headquartered in Beijing and its main competitors are Amazon.cn (or Amazon China, formerly Joyo.com) and JD.com (or Jingdong, formerly 360buy.com). The competition escalated into a price war in December 2010, with each retailer marking down a wide range of items, especially books. DangDang made an IPO on the NYSE in November 2010, estimated at approximately US$1 billion.

Dangdang's main product categories include household merchandise, cosmetics, digital, home appliances, books, audio, and dozens of clothing and maternal and child categories. There are over 10 million new registered customers per year in Dangdang . More than 100 thousand people buy things from Dangdang each day. There are about 30 million people a month browse different kinds of products each month. The monthly sale of goods in Dangdang is over 20 million.

Dangdang sells over 200,000 kinds of books and 10,000 kinds of software and audio products, which make up 90% of the category in China mainland. There are about 3,000 employees in Dangdang, and its customers are among 50 countries, and over 40% B2C customers in China have shopping experiences with Dangdang.