<p>It is crucial to grasp the spatial evolution characteristics of water chemistry and to quantify the contribution rate of different factors for the precision management and secure utilization of water resources in the basin. In this study, river water samples were systematically collected from the Duliujiang River Basin, the concentrations of anions and cations were measured, and the spatial evolution characteristics and ion sources of the watershed were studied by using hydrochemical diagrams, multivariate mathematical statistics, and the absolute factor analysis–multiple linear regression receptor model (APCS-MLR), and the contribution rate of different sources to the hydrochemical components of the basin was quantified. The results indicate generally weakly alkaline water throughout the Duliujiang River Basin. While hydrochemical types exhibit spatial variability, the Ca–HCO₃ type predominates. The chemical composition of river water in the Duliujiang River Basin is governed by rock weathering, cation alternating adsorption, mineral dissolution/precipitation, and anthropogenic influences, and the APCS-MLR model results show that mining wastewater discharge, rock and mineral dissolution, industrial activities, agricultural activities, and unidentified sources (inferred as groundwater recharge) are the main sources of river solutes. The contribution rates of municipal factors, mining factors, agricultural factors, geological factors, and unidentified factors to the river water were 16%, 28%, 19%, 23%, and 14%, respectively, while the total contribution rate of anthropogenic factors (including municipal factors, mining factors, and agricultural factors) exceeded that of natural factors, reaching 58%, and have become the principal driving factors of hydrochemical evolution in the Duliujiang River Basin.</p>