Abstract: Taking Wujianfang west No.1 mine in Inner Mongolia as the engineering background, XRD mineral diffraction analysis, combined determination of liquid-plastic limit and laboratory mechanical test were carried out on three groups of weakly consolidated soft rocks with different clay mineral content from the mine. According to the physical and mechanical test results, three different numerical analysis models of clay mineral content of rock roadway were set up, and the influence of rock clay mineral content on surrounding rock deformation and plastic zone of roadway was studied. The results show that with the increase of clay mineral content, the color of weakly consolidated rocks gradually deepens, the liquid limit and plastic limit gradually increase, the mechanical strength increases before it decreases, and the meso-scale structure develops more and more. The range of plastic zone and deformation of weakly consolidated formation roadway do not increase linearly with the increase of clay mineral content, and the increment of plastic zone and deformation gradually increases. When the content of clay mineral exceeds 33%, the stability of surrounding rock decreases obviously.