There are a large number of conceptual hydrologieal models ayaliable today. It is not casy to immediately identify the similarities and differences between the different models. The Swedish HBV model and the Chinese Xinanjiang model are two examples of conceptual, semi-distributed, rainfall-runoff modols. The Xinanjing model was designed for use in humid and semibumid regions, with no routine for the sbiwmelt runoff, whereas the snow routine is an important part of the HBV model in many applieations. The model structures of the two models may be deseribed in four routines, compared in this paper. Ther integral atructures of them are similar, but there are some differences, eapecially in the runoff production routine. The physical significance and physical definiticns of some model parameters were analyzed. Both models were tested in two basins. Both models gave similar results, and both models performed well in the application. The similarlty of the reaults obtained by different model structures leads to the following two conclusions. First, model stryctyres leads to the following two conclusions. First, more effort should probably be spent on the improvement of input data quality and covernge than on the development of more detailed model strue tures only. Second, inference abou basin behavior and characteris ties form the values ofcalibrated model parameters most be made with great caution.