Fengguo Temple in Yixian County is part of the royal monastery of the Liao Dynasty. The Grand Hall, the main hall of the temple, is a Liao building, the walls of which are full of murals of a grand scale and unique drawing techniques. It is of great value for the study of murals of the Yuan Dynasty. However, due to the serious damages caused by war, earthquake and other disasters, the preservation status of murals is quite worrying. Because of the difficulty in protection and the unclear mechanism research, it is impossible to carry out physical protection and restoration at present. Therefore, we tried dealing with the diseases of mural lines, pigments and structures in a virtual way using Photoshop. The contents of the virtual restoration include cleaning the mural surface covering, completing the missing parts of lines and colors, and correcting the discolored and faded areas. The results show that the restoration of the image has achieved good effects. Photoshop virtual restoration is a feasible and effective method for mural protection. It can not only provide references and lessons for subsequent physical protection, but also extract the value of murals to the greatest extent and be conducive to the display.