Objective To investigate the effects of changes in elastic modulus of dental implants on stress distributions in implants and peri-implant bone by 3D finite element analysis, so as to supply experimental evidence for new implant system. Methods The model of the mandible with implant bone was constructed based on CT data. The elastic modulus of implants was set as 110, 90, 70, 55 and 40 GPa, respectively. The model was applied with static load of 300 N in vertical direction, 100 N in horizontal direction and 130 N in oblique direction, respectively, to stimulate occlusal state. The stresses on different parts of implants with different elastic modulus and peri-implant bone under 3 kinds of loads were calculated and analyzed. Results As the elastic modulus of implants declined, stresses in cortical bone around implants under horizontal and oblique loads decreased, and stresses in the implants showed a decreasing tendency as well. Conclusions The decrease in elastic modulus of implants can benefit the transferring of load from the implants to the surrounding bone, and reduce the risk of long-term implant failure.