Effection of elastic deformation on the dimensional precision of forgings can not be ignored in precision forming process. However, for many finite element methods, it is difficult to extract geometric information of the forgings, which is not conducive to measuring the amount of elastic deformation of mold cavity and forging. Taking the metal forming professional software DEFORM-3D as example, a new method was proposed to measure the amount of elastic deformation based on grid nodes of solid surface. The program based on the method was written with Visual C++ and was used to analyze the elastic deformation in cold forging process of spiral bevel gear. The results show that the method is correct and feasible to study the elastic expansion of mold cavity under high pressure conditions and springback of forgings after unloading.