This paper conducted experimental tests and theoretical analyses to present a comprehensive study on the shear behavior of dry-connected steel plate frame-reinforced brick walls. One unreinforced brick wall, one brick wall reinforced with steel strips, and four brick walls reinforced with dry-connected steel plate frames were fabricated for shear compression tests. Experimental tests showed that steel plate frames effectively improved the bearing capacity and stiffness of masonry structures and impeded cracking. As expected, enhancing the steel plate thickness and vertical load boosted the peak load and axial stiffness of steel frame-reinforced structures but also reduced the ductility. Numerical simulation accurately predicted the peak load, crack development, and crushing area of the specimens. In addition, based on the buckling theory of steel plates and the existing calculation theory of masonry, this paper also proposed formulas for determining the bearing capacity of composite walls. The calculations of the formulas exhibited high accuracy in comparison with the experimental results.