Introduction: Breast cancer is the most common invasive cancer in women worldwide. It also leads as a cause of cancer deaths in this gender. The treatment of breast cancer has been modified significant to conservative treatment owing to the presence of micro metastasis at even earlier stages of the disease. These novel medical treatments are hinged on characterizing breast cancer molecularly. Estrogen receptor (ER), Progesterone receptor (PR), and Human epidermal growth factor 2 receptor (HER2) are the commonest immuno-markers used. Failure of the cancer cells to stain positively for these three receptors, earns a breast cancer the triple negative designation, an aggressive type of the cancer with the worst prognosis. Furthermore the basal subtype of triple negative breast cancer has worse clinical outlook than the non-basal subtype. Characterizing this heterogeneous cancer would aid in choosing appropriate care for individual patients in our locality. This is because African cases of the disease have been associated with poorer survival. Aims and Objectives: To determine the frequency of triple negative breast cancers (TNBC) and their subtypes, at the Jos University Teaching Hospital, between January 2010 and December 2012. And also to further determine the relationship of TNBC to age, gender, histological type, and histological grade. Materials and methods: Histologically diagnosed breast cancers at the Jos University Teaching Hospital, between 2010 and 2012, were retrieved from the archives. Cases with adequate biodata and with sufficient tissue block for immunohistochemistry made up the samples for this study. Archival formalin fixed and paraffin embedded tissue blocks were retrieved. H&E staining was done, to confirm the diagnosis of breast cancer. Immunoperoxidase staining for ER, PR, & HER2 was carried out using the Avidin-Biotin method. Samples with negative staining for these three antibodies were further stained with CK5/6, a basal biomarker for triple negative breast cancers.