Abstract: A model for analyzing spatial discrimination threshold of head-related transfer function (HRTF) magnitudes is presented.First,the position-dependent variations in HRTF magnitudes were evaluated by using a calculated high resolution HRTF dataset.Second,three perceptual-relevant parameters,that is,interaural loudness level difference,binaural loudness level spectra and total binaural loudness level were derived from Moore's loudness model.Finally,spatial discrimination threshold of HRTF magnitudes was effectively predicted through the just-notice-difference of three perceptual-relevant parameters. Results predicted by the model well agreeed with those from psychoacoustic experiments.Therefore,the model is effective for predicting spatial discrimination threshold of head-related transfer function magnitude and applicable to simplify signal processing and HRTF data in virtual auditory display.