Human gall bladders specimens obtained soon after cholecystectomy from 50 patients were observed under electron microscopy. Four types of cells were distinguished by light and electron microscopy in the human gall bladder epithelium, i.e.,"Ordinary epithelial cell", "Clear cell", "Dark cell", and" Basal cell". The Clear cell have been subdivided at least two types by electron microscopy. One was degenerative type and another was immatured one. It was also observed that the mechanism of discharge of secretory granules was the" Merocrine mode". In the cholesterosis, it was assemed that cholesterol was absorbed into the epithelial cells from the bile and accumlated in their basal area, then discharged through their basis. It was taken by phagocytes which gradually transformed into the foamy cells.