Based on ¹⁴C-dating, pollen analysis and physical and chemical data, the formation environment, historic evoluation process and major physical and chemical properties of chestnut soil in the northeastern marginal area of the Qinghai-Tibat plateau were studied. The following conclusions are proved: (1) The soil had already developed during the late-leistocone, but mostly developed in the middle and late Holocene; (2) The herbaceouss pollen in the soil-forming period occupies about 90%, of which Artemisid sp. and Compositae dominate, and small amount of xylophata pollen is found in some regions; (3) The profile structure of chestnut soil is made up of recent soil and paleosol developed in different time; (4) The weak weathering of soil minerals and faint humification of the soil are because of dry and frigid climate in soil forming process.