PURPOSE: This study was undertaken to investigate X-ray mammographic findings which correlated with histopathologic classification of breast carcinomas. MATERIALS AND METHODS: In 114 cases (113 patients) weeviewed X-ray mammographic findings of breast carcinoma and their histopathologic classification, and the findings were analysed to define mass, calcification, and spiculation. RESULTS: According to histopathologic classifications of breast carcinomas, infiltrating ductal carcinoma was the most common(78.9%). X-rays mammographyrevealed that irregular mass was found in 43.9% of cases, calcification in 47.4 %, and radiating spiculation in75.4%. Mass with spiculation accounted for 41.2%, and mass with calcification and spiculation for 34.2%. A commonfinding of ductal carcinoma in situ was an ill-defined mass with malignant clustered microcalcification. Infiltrating ductal and infiltrating lobular carcinomas showed irregular masses with spiculation and colloid or medullary carcinomas had well-defined masses. CONCLUSION: Mass with spiculation, and mass with calcification and spiculation were common findings of breast carcinoma. The differences in X-ray mammographic findings among each different histopathologic type of breast carcinoma are helpful for differential diagnosis.