To reach the motive force requirement of high altitude light aero-plane, a two-stage turbo charging system matching design analysis was performed for a turbo charging piston aero-engine. The software package of AVL boost was used to establish a theoretical analytic model of the supercharged prototype engine. The model was verified and validated though experiments. The model of two-stage turbocharging engine was set up on the basis of the model of prototype engine, and the matching calculates had been done. The characteristics of engine in different altitude above sea level were calculated, and the effects of engine major parameters for the performance were analyzed. The rule of the bypass valve regulating the two-stage turbocharging system was studied. The variation trend of high and low stage compressor-s total pressure ratio versus the different altitude was defined. The result shows that the two-stage turbocharging system can provide high boost pressure, which can be maintained the requested engine power. These work reaches the anticipated design object.