The conservation and restoration of wall-painting is one of the important part of the conservation project of Sajia Temple. According to the Principles for the conservation of Heritage Sites in China ,we have laid emphasis upon a careful investigation of the site condition and then combining with the laboratory study, the field testing study of conservation and restoration of wall-painting in sajia Temple had been completed. The topical deteriorations distributed in the stone wall and rammed wall were chosen. These deterioration facts include detachment and crack of the plaster, flaking of color layer, decay by salts of the plaster. Based on the basic conservation principles of wall-painting which are maximum compatible of the conservation material and minimum intervention, the chosen tests of the conservation materials and techniques were successfully carried out.