Background: Tumour infiltrating lymphocytes (TILs) play a major role in many solid tumours. Expression of Oestrogen Receptor (ER), Progesterone Receptor (PR) and Human Epidermal Growth factor Receptor 2 (HER2) in breast cancer plays strong association with treatment outcome. Treatment options for Triple negative breast cancer (TNBC) is limited. Recent days, Tumour infiltrating lymphocytes (TILs) play a major role in Triple negative breast cancer (TNBC). Methods: 100 cases of Modified radical mastectomy specimen of breast cancer were chosen from surgical pathology records .formalin fixed paraffin embedded tissue samples. Patient’s age, sex, Grade and status of Estrogen Receptor, Progesterone Receptor, and HER2 were assessed and evaluated for Tumor Infiltrating Lymphocytes with Immunohistochemical stains CD45 and CD3. Results: In this study, 31 % cases Showed 50-90 % Stromal TILs 51% of cases showed 20-40% TILs and rest 16 patients had less than 10% TILs.In our study coming to hormonal status 13% showed ER+ /PR-, 22% showed ER+ /PR+ ,18% showed HER2NEU positive , 29% showed triple negative and 18% showed triple positive. Triple negative breast cancer and HER2 positivetumours showed more number of stromal TILs.Stromal Tumor Infiltrating Lymphocytes have strong association with triple negative breast cancer. Conclusion: Tumour-infiltrating lymphocytes are white blood cells that have left the bloodstream and migrated into a tumour. They are mononuclear immune cells, a mix of different types of cells (i.e., T cells, B cells, NK cells, macrophages) in variable proportions, T cells being the most abundant cells. They can often be found in the stroma and within the tumour itself. Tumour infiltrating lymphocytes emerging as host antitumor immune response in triple-negative breast cancer.Among the ER, PR, HER2neu status, most of the TILs were expressed in triple negative tumors in this study.