Human has the ability to attend to a single interested speech in a noised condition and this ability can be improved in the presence of binaural cues.In this paper a speech separation method is presented based on sound localization and auditory masking effect.By two important parameters-the interaural time differences (ITD) and interaural intensity differences (IID)-we estimate the binary masking coefficients in corresponding time-frequency regions.The coefficients are helpful of speech separation by holding interested signal and reducing noise signal.Experiments indicate that the approach described here is efficient not only for voiced speech but also for unvoiced speech and it has more extensive applications than pitch-based speech separation algorithms.