Abstract: The Blind Source Separation（BSS） can turn linearity convolution model in time domain into the instantaneous fixed one in frequency domain by STFT transform.The traditional instantaneous fixed algorithm has indeterminacy in permutation problem and scaling problem，so as to make the signal mixed again after the converse STFT transform.In this paper，based on the study on the structure of separated matrix，a conception of neighbor frequency breadth-angle ratio is proposed，which may contribute in correcting the structure of separated matrix in the frequency that occurs permutation errors.The simulation results show that such compositor algorithm based on neighbor frequency breadth-angle ratio can correct most permutation errors and conclude an exact signal in the blind source separation.