In order to propose a method to determine the characteristic frequency/wavelength of rail corrugation from the perspective of wheel-rail micro stick-slip features, firstly, a complete numerical model of vehicle-track coupling system was constructed according to the actual situation of the metro line, and its effectiveness was verified. Then, with the help of the above model, the stick-slip characteristics of wheel-rail system under the condition of smooth rail surface in the small radius curve were analyzed according to the timefrequencynephogram of the adhesion coefficient, which could be used as a reference for subsequent analysis. Finally, the time-frequency variation characteristics of the adhesion coefficient under conditions of different harmonic corrugation wavelengths and wave depths were compared and analyzed, and an effective method to determine the characteristic frequency/wavelength of rail corrugation based on the time-frequency properties of the adhesion coefficient was proposed. The results indicate that in the presence of harmonic conditions, the timefrequency nephograms of longitudinal and lateral adhesion coefficients of inside and outside wheel-rail interfaces show the corresponding characteristic frequencies and multiple frequencies, and the amplitude of the adhesion coefficient decreases gradually with the increase of the frequency. Under the condition that the wave depth of harmonic corrugation is fixed, the overall stick-slip vibration degree of wheel-rail system decreases with the increase of the wavelength; under the condition that the wavelength of harmonic corrugation is fixed, the overall stick-slip vibration degree of wheel-rail system increases with the increase of the wave depth, and the increase of the wave depth has a greater influence on the small radius circular curve section. The method ofdetermining the characteristic frequency/wavelength of corrugation based on the time-frequency properties of the adhesion coefficient can be used as an effective approach to determine its characteristic frequency/wavelength in the current theory of stick-slip vibration of corrugation.