Objective: The aim of this study was to investigate effects of immediate loading on peri-implant bone reconstruction. Methods : 26 endosseous implants in 8 patients were classified into two groups, including the groups of immediate loading and delayed loading. Digital Panoramic X-ray examination was employed to examine the quality and quantity of peri-implant bone. Results: In the group of immediate loading, the bone density was increased in both the marginal alveolar area and the peri-implant area. And the decrease was more evident in the immediate loading group than that in the delayed loading group. Conclusion: The choice of appropriate prosthesis treatment is very important for bone rehabilitation, especially to patients with implants under immediate loading.