High-power semiconductor lasers are widely used in optical communication, laser processing, laser display, and other fields because of their small size, light weight, and high efficiency. The output power stability of high-power semiconductor laser depends on the current stability of the driving power supply. Based on the current negative feedback circuit principle, this paper realizes the constant current control of the high-power semiconductor laser drive power supply, theoretically analyzes the main factors affecting the long-term stability of the output current of the drive power supply, and experimentally adopts high-precision voltage reference source, low-temperature drift sampling resistance, water cooling sink and so on. A driving power supply with continuously adjustable output current between 0 and 12 A is designed. When the output current is 12 A, the current stability reaches 66.7×10-6 within 10 h. At the same time, the drive power supply with delayed start, current limiting protection, short circuit protection, and other functions, can fully meet the requirement of the stable operation during a long time for the high-power semiconductor laser.