Abstract: According to the X ray diffraction, rock thin section, scanning electron microscope, rock physical property and other testing data, the physical property features of reservoirs and the types and formation mechanism of secondary pores for the Triassic sandstone of the Tulufan Hami Basin were discussed and expounded in detail. The comprehensive analyses showed that the Triassic reservoirs of the Tu Ha basin are mainly the Middle Upper Triassic feldspathic litharenite,and the pore types are dominated by secondary pores. As the reservoirs have relatively poor physical properties, they belong to medium porosity and low permeability or low porosity and low permeability resrvoirs on the whole. During the diagenesis of the Triassic sandstone in the Tu Ha Basin, the more favorable fissure solution typed secondary pores were developed, which constitute the major hydrocarbon bearing space types of the Triassic sandstone in the Basin.