In the context of China's promotion of ecological civilization construction and the goal of "double carbon", carbon dioxide and water vapor concentration monitoring is of great significance, and TDLAS (Tunable diode laser absorption spectroscopy) gas detection technology has developed rapidly and has advantages. A frequency division multiplexing TDLAS laser drive system with STM32H7B0 as the main control chip is designed in this experiment. Using frequency division multiplexing technology, the main control circuit drives the laser to detect two gases at the same time. The system uses STM32H7B0 as the main control chip, uses two DA channels inside the chip to generate modulation waveform, and realizes V-I conversion through AD8051. The experimental circuit uses NOR Flash series SST26VF064B memory chip to realize waveform parameter matching data storage. At the same time, the modulation signal parameters of DA output are adjusted by the upper computer to realize the control of the laser output modulation signal. The experimental results show that the maximum absolute error of the waveform signals of the two DA channels is less than 0.5%, which can meet the requirements of the system and realize the stable signal driving of the laser.