Epididymal spermatzea of mink were used to study the ceallurar localization of several enzymes. Very strong acid phosphatase activity was found in the equatorial region of the head and tail(middle and principal pieces) of spermatozoa while strong activity was found in the galea dapitis, acrosome, and postacrosomal sheath. Strong alkaline phosphatnse activity was detected in the galea capitis acrosome, post-acrosomal sheath and tail. The activity of glucose-o-phosphatase and 5-nucleotidase were confined to the middle piece. The reaction of glucoseo-phosphatase was very strong while that of 5-nucleotidase appeared weak. The activity of ADPase and ATPase was distributed strongly in the tail and it was localized weakly in the acrosome and postacrosomal sheath. The galea capitis was weakly stained by ATPase. Most phosphatases were localizd in the acrosome postacrosomal sheath, and tail, with the exception of glucose-6-phosphatatase and 5-nucleotidase which were confined to the middle piece. Weak non-specific esterase activity was located in the base of the head and middle piece. The activity of DOPA oxidase was weakly spread in the acrosome, postacrosomal sheatin, and tail. Although the activity of malate dehydrogenase was distribueted in the base of the head and tail, the rest of the dehydrogerase activity examined (succinate, lactate, and isocitrate dehydrogenases except 6-phosphogl accnic dehydrogenase) was confined to the middle piece. The activity of succinate was the strongest among the examined dehydrogenases. The activity of NADH diaphorase was strongly confined to the middle piece. The metabolic enzymes (glueose-6 phosphatase, dehidrogeanses, and NADH diaphorase) were confined to the middle piece, while the activity of malate clehydrogenase was found so be extended to the head base and base and principal piece. The lytic enzymes, acid phosphatase and esterase were localized in the acrosomal portion.