Aiming at the blind extraction of independent sources in linear aliasing signals, this paper proposes an ordered blind extraction algorithm based on Whale Optimization Algorithm(WOA) and Principal Component Analysis(PCA). The algorithm takes the absolute value of the signal kurtosis as the objective function, uses the WOA to calculate the decimation vector, and PCA to reduce the dimension of the mixed signal for removing the components of the extracted signal existing in the mixed signal.Thus the blind extraction is implemented in the order of the source signal kurtosis. Simulation experiments show that the proposed algorithm is effective for extracting blind signals, and the extraction accuracy is high, which has certain practical application value.