Abstract: The flying wing configuration shows high aerodynamic efficiency and nice stealth performance. It represents the future military and civil aircraft development direction. The support interference and local shape deformation effect in the wind tunnel test are extremely complex. There are no general support program and correction method for the flying wing configuration test in the wind tunnel. This paper calculated the sting interference and after-body deformation effect on a calibration model of the small aspect ratio flying wing by numerical simulation method. By comparing with the test results, the numerical simulation results are found to be reasonable and the method is proved to be reliable. This method can be used in support program evaluation and support interference correction for the wind tunnel test. The longitudinal components of force or moment of the sting interference and after-body deformation effect are small compared to the longitudinal components themselves. The lateral-directional components of force or moment of the sting interference can be ignored. The lateral-directional components of force or moment of the after-body deformation effect and the lateral-directional components themselves are of the same order of magnitude.