The aim of this study is to investigate the perception mechanism of environmental sounds in postlingual patients with cochlear implants compared with that in patients with central auditory disorders. Seventeen postlingual patients with cochlear implants were studied; six patients with auditory nerve disease (auditory neuropathy) and ten patients with cortical deafness were selected for the comparison. A taperecorded environmental sound perception test of 24 environmental sounds was carried out. This test is divided into two categories: the category of voice includes human voice, animal and bird sounds, and the category of non-voice includes musical instrument sound, natural sound and artificial sound. The percentage of correct perception of environmental sounds in postlingually deaf patients with cochlear implants was markedly higher than that in patients with cortical deafness, but was similar to that in patients with auditory nerve disease (auditory neuropathy).