Transmission level control is provided to eliminate a sense of disorder during a television conference connecting a multiplicity of locations. In a speech input terminal included in connection between multiple locations, there is provided a speech input means for inputting speech, a communication control means for controlling communication between the speech input means and a communication line, a transmission volume adjusting means capable of stepless adjustment of transmission volume, and a reception volume adjusting means. Thus, the volume adjusting means which has conventionally been provided only at a receiving end is now provided also at a transmitting end to allow stepless volume control, which enables speech output in conformity with the speech level of another entity's terminal.