Opening refers to the first transaction of a certain security on every business day of a stock exchange. The first transaction price is the opening price of the day. According to the provisions of the Shanghai stock exchange, if there is no transaction within half an hour after the opening of the stock market, the previous day's opening price will be the opening price of the day.

Sometimes, when a securities is closed for several days, the stock exchange shall provide guidance price according to the price trend entrusted by the customer to the securities transaction, so as to make the transaction price open as the opening price. On the first day, the securities traded on the market are opened at the beginning of the day.