Signal collected in flutter test with variable progression speed (FTVPS) is usually non-stationary, Round Cocktail Table both its frequency and amplitude changed dramatically with time, especially in the sub-critical state.The common non-stationary signal processing method, such as time-varying parameter modeling can hardly analyze and track the mode of signal precisely under high non-stationary degree.Therefore, an adaptive particle filter method based on non-stationary degree is proposed.The tracking performance under high non-stationary degree of this method is verified by simulation experiment data.The results indicate that Baker Boy Caps the method proposed in this thesis has better precision under high non-stationary degree when compared with usual particle filter.