Based on the ascertainment of deep traps，the deep gas accumulation conditions of Eboliang-Ⅲstructure in Qaidam Basin was analyzed comprehensively by researching on the gas sources of deep zones，the configuration of the caprock condition and hydrocarbon accumulation. The results show that the Yibei sag is the main gas source for the Eboliang-Ⅲ structure and the properties of the Lower Jurassic hydrocarbon source rocks are medium-good. The Lower Jurassic hydrocarbon source rock suffered high degree of thermal evolution，and mainly generated nature gas. The Lower Jurassic hydrocarbon source rock can supply enough natural gas for the Eboliang-Ⅲstructure deep zones. Both the upper Ganchaigou group and the lower Ganchaigou group are mainly shore-shallow lacustrine deposits and delta deposits，in which clastic res? ervoir rocks developed widely with low porosity and permeability. However，these clastic reservoir rocks have good conditions for deep gas accumulation. Because the deep traps are rounded and have extensional lacustrine deposits from the upper Ganchaigou group to the Youshashan group，the Eboliang -Ⅲdeep zones have good isolated intervals and preservation conditions. The Eboliang -Ⅲdeep zones are good for hydrocarbon accumulation where traps were formed in the lower and trapped hydrocarbons in the upper. There is one of the most important reservoir forming periods from the lower Youshashan group depositional stage to the last Shizigou group depositional stage，which matches the time of structure forming. The deep zones have the feature of late hydrocarbon accumulation. The Eboliang-Ⅲstructure is a favorable target for deep gas prospecting in the north of Qaidam Basin.