To make it possible for an enterprise terminal to instantaneously issue an electronic certificate based on member registration information from a portable terminal through a communication line, and to display the electronic certificate according to an image display signal from a signal transmitter.

This electronic certificate display system is provided with a portable terminal for transmitting member registration information to an enterprise terminal, and for receiving and storing membership card information prepared by the enterprise terminal based on the member registration information, and for displaying the electronic certificate based on the membership card information according to an image display signal from a signal transmitter, an enterprise terminal for receiving the member registration information from the portable terminal, and for preparing the membership card information based on the member registration information, and for transmitting it to the portable terminal, a communication line for connecting the portable terminal and the enterprise terminal, and a signal transmitter for transmitting the image display signal to the portable terminal.