On the basis of the original Xin’anjiang model, this study solved the matching problem between sub-catchment and grid channel, and enabled the model to calculate channel routing according to actual river conditions. A hybrid rainfall-runoff model(named XAJ-DCH)was further proposed by coupling the XAJ model with diffusion wave method and Muskingum-Cunge-Todini(MCT)method by accounting for the lateral inflow. The flood prediction capabilities of the traditional XAJ model and the XAJ-DCH model were compared at hourly scale for the Chengcun catchment. The performance of both models is comparable and satisfactory, and thus, the rationality of the new model is verified. By improving the channel routing method in the Xin’anjiang model, the spatiotemporal variability can be further considered. Furthermore, compared with the Xin’anjiang model, the XAJ-DCH model can not only be used to simulate the discharge at the outlet station, but also to predict the water level and discharge of the interior station in the catchment. In addition, the diffusion wave method was introduced into the XAJ-DCH model, which can improve the prediction accuracy in hydraulically mild slope area by accounting for the backwater effects.