The invention provides an electrochemical stabilization direct-current power supply device for soft rock. The input end of a three-phase alternating current contactor is connected with a three-phase alternating current line, while the output end is connected with a high-frequency three-phase adjustable voltage-stabilizing current-stabilizing switching power supply, the input end of a three-phase alternating current leak source protector is the same as that of the three-phase alternating current contactor, the output end of the three-phase alternating current leak source protector is connected with a solenoid of the three-phase alternating current contactor, the input end of the high-frequency three-phase adjustable voltage-stabilizing current-stabilizing switching power supply is connected with the three-phase alternating current contactor, the output end of the high-frequency three-phase adjustable voltage-stabilizing current-stabilizing switching power supply is connected with a current inverter, the input end of the current inverter is connected with the high-frequency three-phase adjustable voltage-stabilizing current-stabilizing switching power supply, the output end of the current inverter is connected with an electrode, the input end of a digital timer is connected with the high-frequency three-phase adjustable voltage-stabilizing current-stabilizing switching power supply, and the output end of the digital timer is connected with the current inverter. The power supply and the current are continuously adjustable. The device saves electric energy, and the strength of the soft rock is improved by more than between 50 and 100 percent.