Abstract: Based on low-cycle and reverse horizontal loading test of six 1/2-scaled energy–saving block & invisible multi-ribbed frame walls, the equivalent-elastic-plate mechanical model of the walls in the elastic stage was established. The model considers the construction details of energy–saving block & invisible multi-ribbed frame walls, and includes two orthotropic composite materials calculation model. Then, the walls was modeled simply using an isotropy calculation model, and practical design formulas for elastic module and shear module were given, which provide necessary parameters for the practical design formula for elastic rigidity. The formula of elastic lateral rigidity was calibrated using test results, and the practical design formula for elastic lateral rigidity for energy–saving block & invisible multi-ribbed frame walls was established. The results show that the proposed model can meet the requirement of engineering calculation.