The development of the cochlear aqueduct and its aging change were investiga-ted in 234 temporal bones,ranging from 12-week-old embryo to adult by the lightmicroscope.The width of inner and outer opening,width and length of thecochlear aqueduct were parallel with the advance of fetal age.The length of thecochlear aqueduct at one year old was about the length of adult cochlear aqueduct.The diameter of the cochlear aqueduct at the child was wider than that of theadult.On the basis of morphology of the cochlear aqueduct and its characteristicof age,the developmental rule of the cochlear aqueduct,its function and clinicalsignificance were discussed.