After comprehensive analysis and research of the chemical, trace elemental and isotopic composition of the new types of graveled pore brine discovered in Dalangtan-Heibei, Chahan Slatu, Kunteyi and Mahai in the western Qaidam Basin, it is believed that this gravel-type brine bearing potassium deposit belongs to leaching sedimentary model, and its formation is controlled by the Quaternary gravel deposit and the paleo-halite formation since the Paleogene. The metallogenic model is as follows:the "salt valley" which was continuously formed under drought conditions in the western part of the basin from the Eocene to the Pliocene became the provenance, and then the early Pleistocene sandy-gravel deposit was forming the ore-bearing space. As the surrounding meltwater runoff to the piedmont zone, it would then percolate into the Quaternary gravel deposit with salts that had been leached from the Paleogene halite formation. Under relatively closed conditions, it transformed into high-salinity brine and finally came into gravel-type brine bearing potassium deposit. Therefore, in the future exploration in Qaidam Basin, priority should be given to areas where at the same time developed the deep faults at the periphery of the basin, the Paleogene halite formation and the early Pleistocene alluvial fan bodies.