Primary breast lymphoma accounts for only 0.05%-1.1% of all breast malignancies, and less than 1% of all cases of non-Hodgkin lymphoma. Although primary breast lymphoma may present clinical similarities to breast carcinoma, the majority of cases lack the typical features of breast malignancy or lymphoma. We describe a case of primary breast lymphoma in a reconstructed breast, 8 years after a mastectomy for breast cancer. To the best of our knowledge, this is the first reported case in the worldwide literature of primary breast lymphoma in a reconstructed breast. We will discuss the diagnostic and treatment strategies involved in the management of primary breast lymphoma, and the effect of breast reconstruction on the detection of recurrent breast cancer.