Sclerosing lymphocytic lobulitis (SLL) is a rare inflammatory disorder, which is also known as fibrous mastopathy and lymphocytic mastitis. It is commonly associated with autoimmune disorders, particularly type 1 diabetes and thyroiditis. We report the case of a 28-year-old woman diagnosed as SLL with Hashimoto's thyroiditis, but without diabetes. She presented suspicious microcalcifications without palpable mass in routine mammograms in both breasts. She had been diagnosed as Hashimoto's thyroiditis several years before and had been followed up in endo-clinics.