Take the example of reconstruction project of Yitong River drainage pipelines in Changchun, based on the change of jacking force measured in jacking process by using slurry balance pipe jacking in medium coarse sand formation, the factors affecting jacking force and the changing rule were systematically studied, and the calculation of jacking force were analyzed and compared to the field measured data, finally the measured data were numerically analyzed with Matlab software, calculation formulas of jacking force and friction under the condition of medium coarse sand formation were deduced.