PURPOSE: To provide the performance assisting device for the stringed instrument which enables accurate and easy operation of complicated string pressing on the stringed instrument corresponding to delicate sounding expression and automatically advances the string pressing operation according to specified music.

CONSTITUTION: A CPU 25 drives an actuator 27 by outputting a string depression control signal to an actuator driving device 26 on the basis of chord information and music chord progress information stored in a ROM 23 corresponding to chord name specification information and music specification information specified with a switch group 21 and a music specification switch group 22 according to a string depression processing program stored in a ROM 23. The actuator driving device 26 outputs a voltage signal for driving the actuator 27 to the actuator 27 with the string depression control signal inputted from the CPU 25 and the actuator 8 is applied with a voltage signal (voltage E1 and voltage E2) to put 42 actuators in individual operation, thereby half-pressing or completely pressing a string.