Analysis and discussion the reservoir characteristics of the Middle Jurassic Xishanyao Formation in Niuquanhu area, Santanghu basin, Xinjiang. And find the factors which controlling the physical property of reservoir.Methods:Based on the study of sedimentary facies, by using the casting thin sections, scanning electron microscope, X ray diffraction, micrometer X CT scanning, the constant speed mercury injection and other advanced experiment, the petrological characteristics, the reservoir space types, the size distribution and the geometry of the reservoir are analyzed, finally discussed the control factors of reservoir quality.