Abstract: Based on studies of pore cast thin section, electric scanning microscope, image analysis and mercury injection test of Triassic reservoir of Machangnan area in Turpan-Hami basin, the paper indicates that the pore structure characteristics of reservoirs in this area are not good. They were sorted into four classes. The predominant type of pore structure is middle pore-low permeability-tiny throat. In this area, pore is relatively small, throats are badly sorted, along with capillary curves showing no platform. The influence factors of reservoir are the content of cement and solution.

Key words: Turpan basin, Hami basin, reservoir, pore structure, characteristics, diagenesis