To describe the dynamic characteristics of flight vehicle accurately, a Relevance Vector Machine (RVM) aerodynamic modeling method is proposed. RVM is a learning method which is based on Bayesian learning theory. Compared with Support Vector Machine (SVM), it has the benefits such as probabilistic predictions, sparser model, facilities to select arbitrary basis function and so on. Experimental results show that the proposed method can obtain the aerodynamic model with higher accuracy by less relevance vector. It is also effective and feasible for aerodynamic modeling.