Abstract: A novel signal simulating method based on VBA technique is presented in this paper.Depending on the actual circuit of signal processing,mathematical equations between the input signal and the output signal are established according to the Kirchhoff Current Law.After equations reducing,a mathematical model between the input and output is also built by using the numerical differential method.And then,some simulating works of actual circuits are implemented such as RC integral,CR differential and Gaussian shaping circuit.The simulating results show that VBA technique applied in signal processing circuit simulating is feasible.