In the production practice, the signal gathered by sensor often includes strong ambient noise, and its composition is complex. Focusing on the trouble that traditional methods are difficult to separate and extract fault frequency from strong background noise, a novel compound fault blind extraction means based on improved sparse component analysis (ISCA) and improved maximum correlation kurtosis deconvolution (IMCKD)-named ISCA‐IMCKD- is suggested. Initially, the signal that the sensor has collected is shifted into time-frequency area signal by short-time Fourier transform (STFT). In addition, the single source domain characteristic data is screened by improved single source point detection (ISSPD) to decide the number of sources. Secondly, ISCA method is optimized by using cosine distance improved fuzzy C-means clustering, which is utilized to further process the characteristic data to calculate the mixing matrix. Moreover, estimated source signal is initially extracted according to the membership degree of clustering results. Finally, estimated source signal is shift into the time area by inverse STFT transform, and the IMCKD is employed to enhance the characteristics of the projected source signals. Meanwhile, initially estimated source signal is completely separated, and the defect frequency of the composite faults are finally extracted by envelope analysis. Simulation experiments and measured data are employed to certify the viability of the proposed means. The defect detection of rolling bearings is finished while the time cost is significantly saved.