Abstract: The thrust aerodynamic correction of an aero-engine in an indoor engine test cell is researched under the rating state, the maximum power state and the full afterburner state. The work is based on a 3D computational fluid dynamic (CFD) method with NUMECA software and it includes a preliminary validation about calculation accuracy. The results demonstrate that the flow of air in the indoor engine test cell is predicted successfully, and the thrust correction terms are reasonable and reliable in the trend and range of values. Under high engine mass-flow conditions, Inlet Momentum Drag has significant impact on thrust correction. At the same time, Additive Drag and Suction Drag also affect the thrust correction to some extent.