The invention discloses a method for supporting mold plates on two inner sides of a deformation joint of a shear wall. By setting a stool support (3) for supporting an inner mold plate of the deformation joint at the bottom of the deformation joint of the shear wall; the distance between the two mold plates is limited a rigid support (2) between two large formed mold plates in order to ensure the width of the deformation joint. The method greatly reduces the probability of the mold raising and exploding. The mold plates are high in rigidity, patchwork is tight, the size of concrete forming is precise, and appearance is good. The mold plates are convenient and fast in installation, reinforcement and removal, and can be used many times, and resultantly cost is significantly saved. No filler in the deformation joint is ensured to guarantee to the structural function of the deformation joint. Finally, the construction quality of the shear wall on both sides of the deformation joint is ensured, and the component dimensions are uniform, and the verticality and flatness as well as the overall appearance quality of the concrete meet the acceptance requirements.