In order to further analyze hydrochemical characteristics and controlling factors of Wenquantang, choosing 25 years of water sample testing data from 2000 to 2024, by using principal component analysis method, a systematic study has been carried out. It is showed that mean value of cation concentration in geothermal water is Na+＞Ca2+＞K+＞Mg2+, mean value of anion concentration is Cl＞HCO3＞SO24, and the water chemistry type is dominated by ClNa type and Cl·HCO3Na type without significant changes. Four principal components can be extracted. The cumulative variance contribution is 82.328%, which comprehensively represents the influence of waterrock interaction on geothermal water over a long period of time, long distance and deep circulation. It is in line with actual situation. The study results can provide scientific basis for sustainable development and utilization of Wenquantang.