The diagnosis of musculoskeletal tuberculosis remains a challenge for clinicians and requires a high index of suspicion. The combination of indolent onset of symptom and signs with histological or cytological features and compatible radiography findings, strongly suggest the diagnosis. Prompt diagnosis and treatment are important to prevent serious bone and joint destruction. Tuberculosis involving ribs and presenting with breast mass is a very rare entity and only a few cases have been reported in the literature previously. We present a case of 30-year-old female having tuberculous involvement of the costochondral junction and presenting as a lump in the lower inner & outer quadrant of right breast. Surgical exploration and histopathological evaluation revealed costochondral junction tuberculosis and secondary abscess formation in the right breast. The lump was located in the breast rather than the usual retromammary location, when arising from chest wall or internal mammary nodes. This unusual manifestation of tuberculosis should be included in differential diagnosis of patients presenting with a breast mass and high risk of tuberculosis.