Market dates back to 1986. It evolved and grew along with the shareholding system reform in state-owned-enterprises (SOEs) and in response to SOE development. The Main Board underwent three stages of development: preparation and establishment, adjustment and rapid development, and deepening and improvement. In spite of the suspension of IPOs in July 2000, SZSE Main Board has witnessed continuous improvement in quality thanks to concerted efforts from market participants. With enhanced financing function and issuers' corporate governance structure, Shenzhen Main Board has continuously expanded its capacity to serve the real economy. As of 31 December, 2020, there were 472 A-share companies listed on the Main Board with a total market capitalization of RMB 3.1 trillion(USD 492.1 billion).
As one of China's two main boards and with the support of modern technology, it has turned into a securities market with nationwide reach in the last two decades and become a vital financing channel for major enterprises. Vanke, CIMC and many other listed companies have become global leaders in their industries. The Main Board market has played an important role in promoting modern enterprise system, optimizing resource allocation, readjusting economic restructure and facilitating economic growth.
In February 2021, Agreed by the Chinese state council and approved by the China Securities Regulatory Commission, SZSE started preparation for the merger between the Mainboard and the SME Board. Under the principle of “two unification and four maintenance”, business rules and operation and supervision mode of Mainboard and SME board will be unified while such four factors as issuance and listing conditions, investor threshold, trading mechanism and securities code and abbreviations will stay unchanged. The merger will let SZSE having the Main Board and the ChiNext board in a dual-sector structure which is simpler and more distinctive.