As the main component of modern airplanes, the efficiency state of avionic-complex is very important for combat mission. Based on Markov model, the effectiveness of avionic-complex was modeled for evaluation. Through analysis of its mathematical model of technology state when completing combat mission and the application of stochastic process theory proved the feasibility of Markov model assessing avionic-complex and the evaluation model was established. Finally, a simulation calculation example that avionic-complex completing navigation task validated the model. The correctness of Markov model was proved, and some improvement measures were given.