This r esearch was designed to find the specific and economic methods of diagnosis about malignant melanoma For this study, we selected a typical case that was ambiguous in diagnosis between malignant melanoma and simple mela notic pigmentation, Tissue sections was st ained by H&E method, and immunohistochemical analyses was performed about 8-100 protein and MART-1 molecule, This research showed that MART-l had a more specificity for melanocytes than 8-100 protein , Patterns of MART-1 molecule distribution was more helpful in estimation of malignancies than 8-100 protein distribution patterns, On the basis of diagnostic usefulness and economical aspects, 8-100 protein and MART-1 molecule showed synergis tic and complementary relationship in confirming of tumor origin and they would be much useful for accurate diagnosis of malignant melanoma