In order to investigate the reinforcement effect and calculation method of stone arch bridge strengthened with injecting high performance cement composite concrete, an unreinforced stone arch bridge model and an load-carrying stone arch bridge model strengthened by injecting high-performance cement composite concrete were made for the destruction test.The experiment results show that the ultimate compressive bearing capacity of stone arch bridge model strengthened by injecting 60mm high-performance cement composite concrete can be improved by 25%, when the sustained load reaches 70% of the failure load.Strengthening stone arch bridge by injecting high performance cement composite concrete can effectively improve the failure load and properties of brittle failure, which is an economical and effective arch bridge strengthening method.The calculation results of strengthening arch bridge bearing capacity were in good agreement with experimental results, and the calculation method can be employed to design in strengthening engineering.