Abstract: The failure criteria for masonry are important to define the shear strength of masonry wall under the action of vertical compression load and horizontal shear load. Through comparative analysis, the failure criteria suitable for masonry under shear-compression load are proposed, which are based on the maximum principal stress theory, shear-friction theory, Mohr theory and deformation energy theory. The shear strength formulas of masonry wall are derived according to the failure criteria for masonry, and the differences between the micro-unit and macro-scale Wall-modelling are considered. At last, the comparisons between theoretical values which are calculated by these formulas and test values which are observed in the test of 111 pieces fired common brick walls are performed. And the shear strength formulas for multi-story masonry walls are provided.