The stress sensitivity evaluation of high temperature and pressure gas reservoirs is very important for the correct understanding of the true physical change characteristics of reservoirs and the reasonable design of development plans under the condition of formation temperature and pressure. Three core samples from Yingqiong basin were used to study the relationship between porosity, permeability and net overburden pressure in stress sensitivity test at 140℃ and 70 MPa. The results indicates that the relationship between porosity, permeability and net overburden pressure can be well characterized in the form of a power function, and can be divided into three stages, the corresponding reduction rate of pore-permeability parameters is about 36:13:1. The stress sensitivity of rock samples has nothing to do with the foundation porosity and permeability, but has something to do with the mineral composition and microstructure. The lower the content of the hard component, the stronger the stress sensitivity of the porosity. The lower the content of the hard component, the smaller the throat radius, and the stronger the stress sensitivity of the corresponding permeability. Under the same conditions, the permeability stress sensitivity of the same rock sample is obviously higher than that of its porosity stress sensitivity, and the difference between them is nearly 4~10 times. Compared with the conventional evaluation method, the porosity and permeability stress sensitivity obtained by taking the porosity and permeability parameters under formation condition as the starting point will be reduced by about 65% and 38%, respectively. This paper provides experimental support for the study of stress sensitivity of high temperature and high pressure sandstone reservoirs in this area.