Abstract: To investigate the hydrochemical characteristics and controls of surface water and groundwater in Chen Lake Wetland, the water samples of inflowing rivers and main lakes were collected and analyzed in August (rainy season) and December (dry season) 2020. The results showed that the surface water was neutral to weakly alkaline. HCO₃^- and Ca₂⁺ were the most abundant anions and cations, respectively, and the main hydrochemical type was HCO₃-Ca. Surface water components were mainly derived from weathering and dissolution of carbonate rocks and silicate rocks, and were also influenced by cation exchange. The spatial variability of surface water compositions increased from wet season to dry season due to weakening hydrodynamic conditions. The chemical composition of surface water in the wet season was affected by agricultural activities and domestic sewage, and was affected by industrial and mining activities in the dry season, respectively. These observations demonstrated how the hydrochemical composition of the wetland was controlled by a combination of natural factors and human activities.