An identification method has been developed to extract all the flutter derivatives defined by R.H. Scanlan. In the present work, the signals of the coupled vertical torsional free vibration of the spring-suspended section model are used. The fiutter derivatives of a thin plate obtained using the present method are compared with the corresponding Theodorsen theoretical values. The present method is then used in the identification of flutter derivatives of the Jiangyin suspension Bridge over Yangtze River. The flutter critical wind speed of this bridge obtained from the full bridge aeroelastic model test in a wind tunnel shows good agreement with the estimated result from Scanlan's flutter analysis method with the flutter derivatives using the present method.