The invention discloses a binaural sound source localization method based on a BP neural network. The method extracts the cross correlation function of a binaural sound signal and the inter-aural intensity difference as a characteristic parameter, and models the characteristic parameter by a backpropagation BP neural network. In a test course, according to the cross correlation function of the binaural sound signal and the inter-aural intensity difference, the sound source orientation of each frame of binaural sound signal is estimated by using the neural network. Compared with the prior art,the method is obviously improved in robustness and accuracy.