[Objective] The characteristics and relationships of hydrochemistry in soil infiltration water (SIW) were studied in order to reveal the relationship between the changing ratios of Ca, Mg, and Sr in the karst water and the climate outside the cave.[Methods] Regularly monitoring, sampling, and experimenting on the four cave water pots and the overlying three SIW points in Mahuang cave, Suiyang County, Guizhou Province. Then, statistical analysis methods and comparative analysis of various monitoring indicators by the element ratio method were used.[Results] ① The main hydrochemistry indexes of the SIW showed dry season > rainy season, whilst the cave water showed the opposite characteristics. ② The concentration of EC, Ca²⁺, Mg²⁺, HCO₃^-, and Sr²⁺ in the cave water was about 2~6 times higher than that of the SIW, which indicated that the karst process in epikarst had an important influence on the hydrochemistry elements in the cave. ③ The SIW had a positive response to surface rainfall and temperature changes, the large amounts of mineral elements retained in the soil during the dry season was the main reason for the high concentration of Ca, Mg, and Sr in the SIW in April. ④ The ratios of Mg/Ca and Sr/Ca in the cave water and their correlations reflected the synergy of the cave water by source, water-rock interaction, dewatering deposition of the cave water, prior calcite precipitation (PCP) process, and the main karst process of cave overlying. Therefore, the ratio changes can indirectly show the temperature outside the cave and changes in rainfall.[Conclusion] The hydrochemistry of the SIW and cave water have obvious characteristics of seasonal changes, there are differences between the monitoring pots, and there are significant differences between the monitoring points. The changes in the Ca, Mg, and Sr ratios of the two types of water and their correlations have positive responses to surface rainfall and temperature changes.