The stability and steady speed of the calibration light source directly affect the accuracy and efficiency of spectral radiation calibration of the onboard highresolution spectrometer. To realize the rapidness and stabilization of calibration light source, a fast stabilization regulation method and a system of constant current source based on digital process control are proposed and designed. Based on the constant current source of field effect tube, the rapid constant current source is added with digital process control link to make up for the shortage of feedback oscillation regulation of field effect tube constant current source. The long thermal stabilization time of the system can also be improved. The adjustment method of rapid stabilization can be divided into three stages, including large preset value starting fast preheating to produce heat quickly, buffer fast stabilization to reduce the overshoot oscillation and constant current of simulated closedloop to output the stable current. Comparison experiments between the fast stable constant current source and the field effect tube constant current source show that the time deceases from 670 s to 66s for outputting a current of 1 50000 mA and ripple coefficient 1 decreases from 670s to 66 s. In addition, as the drive circuit of the halogen tungsten lamp of standard light source, the fullspectrum mean baseline drift of the 400 nm~2 500 nm data reduces from 05% to 006% under the output spectrum of the standard light source for 20 minutes after being electrified for 2 minutes.