Abstract: Multi-ribbed composite wall is a new type of wall structure. It has been widely used in civil buildings due to its light weight,good seismic performance,good energy-saving effect,high industrialization and high construction speed. The application of multi-ribbed composite wall in the construction of bunker can not only improve the seismic and thermal insulation performance of bunker,but also improve the thermal insulation performance of bunker. It can reduce the loss of raw materials and achieve the effect of energy saving and environmental protection. The nonlinear numerical analysis of the force performance of the wall model under the action of grain side pressure was performed by establishing a multi-ribbed room type granary composite wall model using the large-scale general-purpose finite element analysis software ABAQUS. In view of the effect of filled blocks on the flexural rigidity of multi-ribbed composite walls under the effect of grain-side pressure,building blocks and non-blocking models were established,and the influence of the filling blocks on the mechanical properties of the multi-ribbed composite wall under the action of grain load was inferred respectively.It was concluded that the filling block had great contribution to the flexural rigidity of the wall. When calculating the deformation of the multi-ribbed composite wall under grain lateral pressure,the filling blocks should be fully considered.