Abstract: Objective To investigate the association between tumor-infiltrating lymphocytes and neoadjuvant chemotherapeutic effect in patients with breast carcinoma. Methods We retrospectively evaluated 59 female patients with breast carcinoma treated with neoadjuvant chemotherapy followed by definitive surgical resection in the First Affiliated Hospital of Nanjing Medical University from December, 2010 to November, 2013. By the method of tumor-infiltrating lymphocyte count score, we counted the total score of intratumoral lymphocytes and stromal lymphocytes before chemotherapy, as well as the stromal lymphocytes after the operation. The pathological responses were evaluated by Miller and Payne (MP) grading system criteria after the operation. Then the correlation between tumor-infiltrating lymphocytes and the pathological responses after the operation were investigated. Results The remission rate of neoadjuvant chemotherapy in the highpercentage tumor-infiltrating lymphocytes group(3-6 level) was more effective than that in the low-percentage group(0-2 level) (P=0.001). The higher stromal lymphocytes percentage after the neoadjuvant chemotherapy had the higher remission rate(P=0.031). Conclusion Tumor-infiltrating lymphocytes have strong correlation with pathological responses to chemotherapy and they would be the important parameters in predicting the remission rate of neoadjuvant chemotherapy.