Based on "two airports in a city" management mode of Shanghai airport, according to actual demand, this paper analyses the feasibility of building a unified information system for passengers' safety. According to the way in which the international and domestic passengers obtain information, it proposes a specific design of the passenger information system security with the idea of software engineering. Experiments are conducted based on the established prototype system, and the results prove that this design can meet the practical requirements and it plays a positive role in gurantee of air safety.