A system in which multimedia information communication is performed between two terminal stations connected to each other through a packet switching network, each of the terminal stations having a control device for performing send control for sending a video packet including coded video data and a voice packet including coded voice data to the packet switching network and supply control for supplying the video packet and voice packet received from the packe switching network to a video codec and a voice codec respectively. One of the two terminal stations operating as a receive side issues a video data transmission mode change request to the other terminal station located at a multimedia information transmission side in accordance with a status of delay of video packets and/or voice packets received from the packet switching network, and the other of said terminal stations changes the video data transmission mode in response to the transmission mode change request, so that when the delay generated in the voice packet arrival interval exceeds a predetermined threshold value, video transmission is stopped and the operation mode is made to be a communication mode of only voice data.