Improving the safety of the approach control system is very important for flight safety. By analysing the risk during the operation of the approach control system, the risk factor set is constructed by using the fault tree analysis method. Then, on this basis, its operation safety evaluation index system is established and the weights are determined by using the fuzzy order relationship analysis method. Finally, the multi-level safety evaluation model is constructed using the extensibility method, and the safety evaluation calculation formula for multiple time periods in a day is given. Taking the operation of Qingdao air traffic control station as an example, the operational safety is evaluated and calculated, the evaluation results are given, and suggestions for improving the operational safety of the control system in recent years are given.