To provide a cyber stock exchange system by which enterprise information can be speedily and exactly provided to a plurality of users when the users are to exchange the stocks of an enterprise online through a network communication net.

This system has the network communication net for mutual data communication by linking a number of unspecified communication networks, a plurality of client personal computes for displaying URL data linking advertisement data and/or web pages on a relevant menu picture, and a main server for providing present stock price-related data in real time, updating, storing the owned stock-related data for each user, storing the advertisement data or the like from individual enterprises, and performing control so that the advertisement data or the like of the relevant enterprise can be displayed in a prescribed area of the relevant menu picture of the client personal computer when a menu item select signal for displaying the enterprise name or item code of the specified enterprise relative to selling and buying of stocks is inputted through a dedicated emulator.