To study clinicopathological characteristic of the breast mucosa-associated lymphoid tissue-type-lymphoma (MALT-ML). MethodsFour cases of the breast MALT-ML were studied by HE staining and immunohistochemical technique (ABC method). ResultsOf 4 cases breast MALT-ML, 2 were CCL type, 1 CCL type with blastoid transformation, monotoid Bcell type. By immunohistochemistry, all cases were monoclonity of B-cell with follicular colonization and lymphoepithelia lesions.ConclusionsBreast MALT-ML has a special pathological morphology.