This article is a review of the current understanding of molecular mechanisms in the regulation of brush border membrane (BBM) hydrolase expression. The promoters of BBM hydrolase genes have a number of binding sites for nuclear transcription factors which may regulate the tissue specific and developmental gene expression. The rate limiting step of BBM hydrolase expression is the posttranslational processing and intracellular transport of the hydrolases. The informations for apical sorting of BBM hydrolases may present in the ectodomain of molecule, while the basolateral sorting signal has been reported to be localized in the cytosolic domain. The disturbance of transcription or posttranslational processing may result in abnormal expression of the particular hydrolase which is clinically identified as a BBM disease.