Castleman’s disease is a rare and complex lymphoproliferative disease with unknown etiology. It can be classified clinically into unicentric or multicentric and histologically into hyaline vascular or plasmacytic variants. Unicentric Castleman’s disease in breast is rarely reported worldwide. We report a case of a young lady presenting with complaint of solitary right breast lump, for which she underwent excision biopsy and was diagnosed of having unicentric Castleman’s disease of breast, hyaline vascular variant.