Abstract: In order to explore the influence of horizontal arch effect in bulk storage on silo wall side pressure, a model was established considering the horizontal arch effect in the storage material. The model is part of the material storage which was surrounded by the silo wall, the sliding surface and the plane composed of balanced arches. The unit micro-element was selected from the model to force analysis. The calculation method of the lateral pressure in the silo wall was proposed, which was considered the horizontal arch effect. The results from this study were analyzed and compared with other theories, finite element analysis, and test value. The results showed that the calculations from this study were slightly larger than other theoretical and finite element results, indicating that grain arch effect could increase the side pressure of the silo wall to a certain extent. The calculated results of this study were basically consistent with the test value, suggesting that the calculation method adopted in this study was effective. In the present study, the calculation method of silo wall side pressure considering arch effect is presented, which makes the side pressure of silo wall more accurate and provides theoretical support for silo design.