Eachcomponentofthehumanearperformsaspecificfunctioninhearing.Theactualprocessofsoundtransductiontakesplaceintheauditoryportionoftheinnerear,thefluid-filledcochlea.Inthecochlea,thesensitivityandefficiencyofsensoryapparatustoconvertmechanicalenergyintoneuralactivity,largelydependsonthefluidicandionicenvironment.Inthelateralwallofcochlea,thesecretoryepitheliumstriavascularisplaysanimportantroleinthemaintenanceoffluidicandionichomeostasis.Avarietyofgenemutationsdisturbsthecochlearhomeostasisandsubsequentlyleadstohearingimpairment.Thereviewcoversseveralaspectsofcochlearhomeostasis,fromcochlearfluidandthefunctionalroleofstriavascularis,cochlearK+recyclinganditsmolecularsubstratestogeneticdeafnesswithabnormalcochlearhomeostasis.