In recent decades, estimation of watershed model parameters is facing problems due to the large number of parameters and lack of complete physical understanding of them. One of the most important parts of modeling in hydrology is the uncertainty analysis of parameters in hydrological models. Identifying the characteristics of the output of the model. In this study, for the hydrological modeling of the Shapur River catchment basin system, the calibration and uncertainty analysis of the hydrological parameters of the WEAP software have been investigated. The calibration was done first by PEST method and then by GLUE coding method and finally it was connected with WEAP software API to analyze the uncertainty of the parameters. The results of the Nash-Sutcliffe efficiency coefficient error standard value in the PEST method for the sub-basins of the Shapur catchment basin are on average 53.0, which indicates the appropriate estimation of these parameters. The calibration and uncertainty analysis of the parameters from the GLUE method compared to the likelihood function of the Nash-Sutcliffe efficiency coefficient With a threshold of 0.8, it showed that, on average, the posterior distribution of the parameters of flow resistance, water capacity of the root zone, and plant cultivation coefficient were smaller compared to their previous distribution. On the other hand, on average, 60% of the measured runoff data in the hydrometric stations of the Shapur catchment area are within the 95% confidence range. The average thickness of this interval is 0.03 for the mentioned basin, which is relatively small and favorable