A simulation equation of surface etching for amorphous materials during ion beam etching was worked out based on the characteristic curve method, and a simulation program named BLAZING for the ion etching process was established according to the holographic grating.Then, the relation between the etching rate of amorphous materials and ion beam incidence was analyzed and optimized. Finally, an experiment was carried out to verify the simulation program with the ion beam etching. By adjusting the etching rate ratio from 2∶1 to 1∶2 for a mask and substrate materials, four 1 200 l/mm blazed gratings with the right angle between 34°and 98°and the blazed angle about 8.6° were fabricated, and the simulation error between the experimental data and the simulation data is less than 5%. By controlling the etching time from 6 min to 14 min, six 1 200 l/mm blazed gratings with the ridge between 0 nm and 211 nm and the same blazed angle of 8.6° were fabricated, and the error mentioned above is less than 1%. The contrast results illustrate that the error of contour line between simulation and experimentation is less than 5%, and the error of etching ending time between simulation and experimentation is less than 1%. It concludes that the simulation program BLAZING can simulate the effect of different etching processes and different parameters on the etching results, and can predict and control the ion beam etching process.