Abstract: Guinan area is located in the water conservation function area of Longyangxia section in the upper reaches of the Yellow River. The mineral water resources are very rich but with low degree of research. This area is basically in a natural state without exploitation or utilization, and the drinking water in some villages and towns is difficult to get. It is of great significance to study its occurrence, distribution and formation mechanism for the sustainable development and utilization of mineral water in this area and to solve the problem of drinking water in scattered villages and towns. The distribution characteristics of mineral water in the study area were systematically sorted out by statistical analysis, water chemical isotope and other graphic analysis methods. The accumulation mechanism of strontium-type natural mineral water was comprehensively discussed from the aspects of water chemistry, isotope and trace element background value of surrounding rocks. The results show that the strontium content in the groundwater in Guinan area ranges from 0.42 to 2.46 mg/L, with an average content of 0.92 mg/L, which belongs to the weakly alkaline strontium mineral water. Its hydrochemical composition is mainly controlled by water-rock interaction, and the background value of high strontium in regional rocks provides the material source for the formation of mineral water. The highly developed bedrock fissures provide a good migration space for the formation of mineral water. The research results could solve the difficulty of water use for some residents and provide a directional target area for the sustainable development and utilization of subsequent mineral water resources, and help the high-quality development of mineral water in Qinghai Province.