PURPOSE: To provide the orchestral accompaniment system which can be enjoyed as a playing method over a wide range by reflecting the motion and speech of a singer in real time on previously generated orchestral accompaniment video information and speech information.

CONSTITUTION: The orchestral accompaniment system uses a chromakey as a composing means for the orchestral accompaniment video information and singer video information, and a video camera 7 which detects a singer 5 and the background 6 and a detection and composition device 8 which reflects the singer video information and background video information obtained by the video camera 7, and singing voice on the orchestral accompaniment device 4 are added to the system constitution of a display 1 which displays the orchestral accompaniment information, a microphone 2 through which a singer inputs a singing voice to the accompaniment of a text on the display 1, a speaker 3 which outputs the singing voice from the microphone 2 while making it correspond to orchestral accompaniment music corresponding to the orchestral accompaniment video information, and an orchestral accompaniment device 4 which controls the display 1, microphone 2, and speaker 3.