Vaginal epithelium of ovariectomized rats following the subcutaneous injection of oestrogenic hormone was analyzed by enzymorphology and particular attention was given to mucin formation. Localization and intensity of enzymes examined in this study such as amylophosphorylase, amylo-1, 4[forward arrow] 1,6-transglucosidase, alkaline and acid phosphatase, 5-nu-cleotidase, esterase, DPNH-diaphorase, and [beta]-glucuronidase varied depending on the stage of hormonal stimulation. Mucified cells contained the various enzymes examined, being especially rich in phosphorylase, alkaline phosphatase, 5-nucleotidase, [beta]-glucuronidase and DPNH-diaphorase. These seemed to be related to the intracellular metabolism in the mucinogenous cells of epithelial layers. One of these, amylophosphorylase was demonstrated only in mucified cells within whole epithelial layers in mucified stage, and a close relationship between it and mucin formation was observed. The location of amylo-1, 4[forward arrow]1,6-transglucosidase resembled the phosphorylase finding and suggests a similar physiologic function.