Due to its low power consumption, small size, high modulation frequency and easy integration, VCSELs are widely used in the field of magnetic detection. As a high-precision sensor, the atomic magnetometer reduces the measurement accuracy due to the unstable output of the laser during the measurement of the magnetic field. A controller that can resist change in ambient temperature was designed to deal with the instability of the output of the laser due to environmental disturbance. Firstly, the high-resolution temperature solution was realized by the ADAU1401A chip with DSP core and DPSD method. Then the temperature control mathematical model was established by means of system identification. Finally, the disturbance observer and internal model control principle were applied to design anti-disturbance and low overshoot robust controller. The experimental results show that the control accuracy of interference is ±0.003 °C at 70 °C, and the control accuracy is ±0.001 5 °C at room temperature, which lays a foundation for stable output of laser and high-precision magnetic field measurement.