Abstract: Based on the airfoil vibration model that can plunge and pitch at different angles of attack, the aeroelastic tests with typical airfoil NACA0012 and NREL S809 were implemented in the low speed wind tunnel, and sufficient vibration response in time domain with different wind speeds and angles of attack were measured. Via analyzing those aeroelastic responses under various experimental conditions，typical flutter and stall flutter were observed. It shows that the angle of attack effects on changes of the state of flutter.