In order to deeply understand the chemical evolution of groundwater and scientifically guide the groundwater resource management in the alpine region, this study took the Golmud River Watershed as the typical alpine watershed, investigated the groundwater chemistry and explored the influencing factors in 2019. Meanwhile, the groundwater quality in the snowmelt, wet season and dry season was evaluated using the entropy water quality index, Durov diagram and sodium sorption ratio, and potential risks posed by nitrate and fluoride in the groundwater to human health were assessed using the mathematical model of health risk assessment. Hydro chemical results showed that chemical type of groundwater had little change with periods but varied greatly in space: HCO^-₃ type for phreatic groundwater in the mountain area, Cl^- type for phreatic groundwater in the plain area and HCO^-₃ type for confined groundwater in the plain area. The high ion concentrations of groundwater occurred mainly in the overflow zone of plain. Phreatic groundwater chemistry was mainly affected by the fertilizer use of spring tillage during the snowmelt season, by the industrial wastewater and domestic sewage discharge during the dry season, and by the water-rock interaction during the wet season. The results of water quality assessment indicated that shallow groundwater was not mostly suitable for irrigation in the watershed, and some was not suitable for drinking in the plain. The health risk evaluation found that the non-carcinogenic risk of fluoride was greater than that of nitrate to human health, and has already endangered children, and the non-carcinogenic risks of fluoride and nitrate were severer to human health during the dry period than other periods. Therefore, it is currently urgent to reduce the anthropogenic input such as domestic sewage, industrial discharge and agricultural discharge to protect the groundwater quality in the watershed.