The static and dynamic characteristics of a small EDM machine were analyzed by finite element method. The influence of the general layout structure of the machine tool on its static stiffness was analyzed and compared.The static analysis and topology optimization for the parts with relatively small stiffness were carried out.Based on Hertz contact theory and Ji-cun-yun-xiao integral method,the dynamic stiffness parameters of the machine tool joint were analyzed and calculated.The dynamic characteristics model of the machine tool was established by using the equivalent spring and damping.The machine first six natural frequencies and mode shapes were extracted.The natural frequency was reduced relative to the rigid connection.The model can be used to simulate the dynamic characteristics of the machine tool more accurately.It provides a basis for predicting the static and dynamic characteristics of machine.