Objective To study the optimal condition of screen printing of diatomite wallpaper, to in order to obtain better printing quality. Methods The optimal printing condition was revealed by orthogonal experiment. The printing pressure, squeegee angle and screen distance were introduced as experimental factors. The effects of these factors on the field density and color difference were discussed by range and variance analysis. Results The results showed that the optimal condition was printing pressure 0.5 MPa, squeegee angle 75°, screen distance 7 mm. Conclusion The printing effect of diatomite wallpaper printed under optimal condition was good, and its tone reproduction curve was close to the ideal curve. This study provides practical basis for actual printing.