In finance the term A share has two distinct meanings, both relating to securities. The first is a designation for a "class" of common or preferred stock. A shares of common or preferred stock typically have enhanced voting rights or other benefits compared to the other forms of shares that may have been created. The equity structure, or how many types of shares are offered, is determined by the corporate charter.

In China, A shares are those in Chinese companies issued in China under Chinese law. They are denominated in Chinese currency, the renminbi, and are listed on the Shanghai or Shenzhen stock exchanges. Currently, only Chinese residents of China may trade the 776 companies listed in Shanghai, and the 489 companies listed in Shenzhen.