Abstract: According to the instability problem of U-shaped steel frame in soft rock roadway, the mechanics principle was applied to calculate the axial force and bending moment with or without internal bracing in U-shaped yieldable steel frame. Combining with the engineering field research, we propose the combined support design type of internal bracing in U-shaped yieldable steel frame and anchor mesh cable. The results show that the max convergence between the two walls of the roadway was about 40.90 mm only and the max convergence between the roof and floor was about 62.45 mm．The deformation of support is not more than 15 mm and the engineering application effect is good.