Three problems are normally found in the spare parts configuration of phased array antenna, namely, the strong redundancy, the batch delivery maintenance and the multi-echelon maintenance. Aiming at these problems, through analyzing the relations among spare parts cost, repair capacity and inventory strategies, an optimal configuration model was established based on the periodic review strategies. Firstly, the repair circulation process of fault component and the periodic supply process of maintenance spare parts were given, and then the system supply availability model was built by analyzing the relations among spare parts, inventories and repair capacity, and the batch arrival queuing theory was also used. Secondly, an optimal configuration model of spare parts was built, which takes minimum spare parts costs as the object and the system availability as the subject. Next, solution algorithm based on the margin analysis theory to the model was also given. Finally, simulations and analysis of an instance were conducted to verify the proposed model, and results show that the model can solve the spare parts allocation problems of phased array antenna well, and has a high superiority. 