The grouting sleeve is commonly used for the reinforcement connection between precast reinforced concrete components. During construction, the compactness of the grout in the sleeve may have defects, affecting the mechanical performance of the connection. The behaviour of the grouting sleeve connection with grouting defects subjected to dynamic tensile loads was numerically investigated in this paper. Finite element (FE) models of the grouting sleeve connection incorporating various types of defects were developed and validated against the test results. A comprehensive parametric study was conducted to evaluate the effects of the steel rebar diameter, the defect type, the rebar anchorage length, and the tensile rate on the bearing capacity and the failure mode of the grouting sleeve connection. The results indicate that the yield load and ultimate load increase with the increase of steel rebar diameter. Defects located in the middle of the connection exhibited a more significant detrimental effect on performance compared to those at the ends. Furthermore, an increase in defect length resulted in decreasing ultimate loads and a shift in failure mode from steel bar fracture to pull-out. This pull-out failure mode was more likely to occur at a higher tensile rate. Considering the influence of the defect type and the tensile rate, a formula was proposed to predict the bond strength of the grouting sleeves. The predicted bond strengths demonstrated good agreement with both the experimental and FE model results.