Wavelet ridge can reveal the information about the instantaneous frequencies of signals. According to the problems of the current multi wavelet ridge extraction methods, a new method for multi wavelet ridge extraction is proposed. After the wavelet scalogram is obtained by continuous wavelet transform, the reassigned algorithm is applied to it, and the reassigned wavelet scalogram is denoised by the singular value decomposition further, then the wavelet ridge of each component in the signal is extracted via modulus maxima of wave-let coefficients. Compared with other methods, the proposed method is better suitable for extracting the wavelet ridges of the multicompo-nent AM-FM signal with low signal-to-noise ratio, in which some components have large carrier frequencies. The result of the application to gearbox fault characteristic extraction verifies the effectivity and practicability of the proposed method.