Primary small cell carcinoma of breast is a very rare variety of breast cancer. There is no defined standard treatment of primary small cell carcinoma of breast in the literature due to rarity of the disease. It constitutes <1% of all breast cancers. Optimal management strategy may include surgery (non– metastatic cases) followed by systemic chemotherapy commonly cisplatin and etoposide based and chest wall irradiation with 50 Gy in 25 fractions, there is no clear guidelines regarding the dose of radiation, therefore it is justifiable to use 50 Gy in 25 fractions. We are reporting a case of right sided primary breast small cell carcinoma in a 34 years old premenopausal female, treated with right modified radical mastectomy followed by etoposide and cisplatin based chemotherapy 4 cycles and chest wall irradiation 50 Gy in 25 fractions. She completed her treatment and regularly on follow up.