A probabilistic model is used to assess the structural reliability of typical reinforced concrete masonry walls under combined shear and compression. Factors such as model error, shear strength of concrete masonry, wall aspect ratio, horizontal and vertical reinforcement ratios, structural safety class, axial load-to-dead ratio, height and thickness radio of the wall, and load effect combination will be considered. Based on a relatively large number of test results and theoretical analysis from the literature, the limit state equation for shear bearing capacity was established. A sensitivity analysis will be performed to identify the key contributors to the reliability of the masonry walls under the combination of gravity and earthquake. The results will provide a base to evaluate whether consistent safety is achieved for masonry walls that are subjected to different load combinations. The counteracting load factors in current design codes for masonry structure will be investigated.