Abstract: Characteristics of the interaction between the support and the test model are inves-tigated in stage separation tests which are carried out in Φ1m hypersonic wind tunnel.The reset zero method is validated in tests.The technical content includes the interaction effects of the sup-port on aerodynamics of two stages with different attack angles and separate distances.The re-sults indicate that the jet height on the underside increases due to the support interaction.The support-induced axis force increment of the first stage is so far smaller than the original value,u-sually less than 2%,and thus there is no need for interference correction.The support-induced axis force increment of the second stage is more than 10% of the original value at different attack angles and stage separation distances so that the correction should be considered.The error between reset zero method and CFD results in the case of separate distance 0.1D(D is the refer-ence diameter of model)is about 0.005 which is lower than other case and acceptable as a whole. Numerical and test results indicate that the interference correction of the normal force based on the zero reference is appropriate for the first stage in the case of 0.1D stage separation distance, but it is not suitable in the case of 0.5D stage distance for the other stages.