The outputs of complex simulation system are characterized by complex, nonlinearity and smoothness. Great risks come into existence when the traditional model validation method is used to solve the above problems. Complexity measure is an important parameter in describing the characteristic of nonlinear time sequence，so the theory of complexity measure is introduced into simulation model validation. Based on calculating the complexity of experiment and simulation data, the validity of model is measured by comparing the complexity measures between the simulation results and experiment data. Finally, an example is given to analyze the conclusion. The result shows that the method is simple in computation， practical and without any special requirement to the length and stationarity of time sequence.