A display-screen-sharing system capable of transmitting data of a display screen appearing on a transmission-side terminal to a reception-side terminal with a high degree of efficiency in accordance with a processing state of the reception-side terminal. The transmission-side terminal includes a search unit and a transmission-side transmission/reception unit. The search unit sets an area to serve as a search object on the display screen. The reception-side terminal includes a reception-side transmission/reception unit for receiving the display-screen data from the transmission-side terminal and transmitting the ready-for-reception signal to the transmission-side terminal.