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Background: Part of tunnel of rail transit of line 1# in Lanzhou city passes through loess. Loess has obvious water sensitivity and anisotropy, these obvious characteristics will have different degrees of influence on different projects. Objective: To compare the differences of shear strength with the vertical and horizontal direction through triaxial and direct shear test, and permeability of samples in different directions. Method: The Q4 loess undisturbed sample respectively from vertical and horizontal directions near tunnel face were selected in order to study the physical mechanical properties of Lanzhou rail transit secent, many related experiments has been carried on. Results: The results show that the anisotropy of the shear strength of the surrounding rock (Q4 loess) is significant near the tunnel face with depth of 15m. The failure stress in the vertical direction is 1.33 times that in the horizontal direction, and the permeability coefficient in the vertical direction is 1.37 times that in the horizontal direction. In different directions, the internal friction angle of loess is basically the same. The cohesion force is different in different directions and different test methods. In general, the vertical strength of Q4 loess is greater than the horizontal strength. Conclusion: This characteristic is caused by the structural characteristics of loess. Therefore, in the design and construction of loess tunnel, the mechanical parameters in different directions of loess should be considered, and the influence of different test methods on the measured parameters should also be considered.