In order to solve the problem that the PCN value of military airport pavement strength evaluation index has many parameters and complex iteration, a practical calculation software is designed. On the basis of Winkler foundation model and elastic half-space foundation model, the PCN calculation formula and reasoning process are analyzed, and two kinds of PCN value solving flow charts of rigid pavement are formulated. Combined with Visual Basic programming language and Visual Basic 6.0 platform, PCN calculation software is developed. By analyzing the advantages and disadvantages of the two calculation methods and their practical application, the corresponding suggestions are put forward. The verification results show that the calculation results of the software are accurate and fast, and it has certain practical significance, and it can also be applied to composite pavement after conversion.