Classical multi-echelon repairable item inventory models are based either on steady-state distribution or infinite repair capacity, which are at variance with real situation. A repairable item inventory model based on limited repair capacity and non-stationary demands was put forward. The system performance measure was analyzed and the model was solved with queuing theory and other related means. Algorithm analysis was carried out with real examples. The results showed that the model can satisfy the lowest system cost requirement and realize the goal of minimal total shortage.