Abstract: Based on Spude calculation principle of the mixed-layer pumping test, this paper has carried out a study on the permeability coefficient of aquifers by single-well mixed-layer pumping test in the No. 5 well in the south of Yanqi Basin, Xinjiang, under the condition of no observation holes and no stratified water stop. By means of graphical method, the static water level of confined aquifer in the lower part of the mixed-layer well is calculated to be 47.232m, and the Q-S curve of the aquifer is plotted. On this basis, the permeability coefficients of confined aquifer and phreatic aquifer are calculated by stratification, and the result is Kb=6.968md-1, Ka=4.979md-1 separately. By comparing with the actual pumping test results, the validity and accuracy of the method are verified. It can provide reference for the calculation of aquifer permeability coefficient in a single-well mixed-layer pumping experiment.