Abstract: To mitigate the insufficiency of the traditional hydrological model in karst hydrological simulation, the Xin'anjiang Hydrological Model was modified by reconstructing a heterogeneous groundwater system with linear reservoirs and introducing the virtual area coefficient of the watershed (f) to modify non-conservative characteristics. The modified Karst Hydrological Model was applied to the Chongling River Basin, a typical corrosional hill region of southern Hunan Province, China. In addition, this study focused on dynamic changes of non-conservative characteristics based on the modified model. The results demonstrate the following:① The modified model outperformed the Xin'anjiang Model in karst hydrologic simulation (by 11.21%) especially in water balance (by 23.29%) and low water flow (by 27.64%); ② The non-conservative status of the karst watershed has duality because of the multi-directionality of the underground confluence system; ③ The area of the underground system is positively correlated with precipitation, while the variation of the area decreases with the increase of the precipitation by the constraint of underground saturation; ④ Inter-catchment water exchange exhibits time lag because of the hydration and water retention of karst.