In order to study the grouting reinforcement effect of structural plane in cracked rock mass under uniaxial compression test and reveal the essence and mechanisms of grouting reinforcement, the roughness of structural plane in cracked rock mass was measured and studied. The influence of grouting on strength, JRC and stiffness was analyzed through shear tests of structural plane of cracked rock samples around grouting reinforcement. Test results were back-analyzed using JRC－JCS mode. The results showed that the JRC of structural plane in artificial cracked rock of the same rock mass was similar and replicable, the JRC value was about 8-10. Stiffness, roughness, peak shear strength (PSS), residual strength (RS), shear strength parameters (SSP) and slope of upward section (SUS) of structural plane were significantly improved by grouting reinforcement. The theoretical formula of structural plane stiffness was given by theoretical analysis.