In this study, the structural analyses were conducted for each model by applying the loads into the design of a large commercial truck seat. Model C with three vertical frames has the smallest total deformation among all models, indicating the strongest stiffness. The maximum total deformation of model C was shown to be 0.68 times smaller than that of model A and 0.79 times smaller than that of model B. The equivalent stress of model C was also shown to be the lowest, indicating the greatest stiffness. The maximum equivalent stress of model C was shown to be 0.8 times smaller than that of model A and 0.91 times smaller than that of model B. At the upper part of the seat or the part where the force was applied, all three models were shown to have the largest total deformations and equivalent stresses. If the result of this study is applied to the design of automotive seat frame, it is thought that the durable and rigid sheets can be manufactured efficiently. By utilizing this study result, the equivalent stress and total deformation are investigated without the real experiment by shape at the seat of large commercial truck, and the durability and rigidity can be seen.