The characteristics of the semiconductor laser current control output optical power change were combined by field effect tubes and precision op amp, and a semiconductor laser power supply control system, power source real-time data acquisition, multiplex current output, feedback adjustment stability. The active temperature control strategy design is used, and the temperature is collected in real time. The control fan speed is compared to the set temperature, ensuring the temperature constant, and further ensuring that the laser output optical power is stable. The test results show that the power control system current is accurately adjustable from 0 to 20A, the modulation frequency reaches 50 kHz, and the output laser power error is controlled at ± 2%, which has the advantages of high frequency modulation performance，stable output and active temperature.