Background: Neutrophil-to-lymphocyte ratio (NLR) has been found to offer clear predictive utility for the overall survival (OS) and pathologic complete response (pCR) in breast cancer (BC) patients receiving neoadjuvant chemotherapy(NAC). However, previous studies mainly focused on pre-NLR. The aim of this study was to explore the role of pre-/post-NLR towards OS and longitudinal NLR kineticsonpCR for BC patients undergoing NAC. And we also tried to build a nomogram for OS prediction based on these parameters. Methods: In this study, we retrospectively collected 501 female patients with locally advanced BC receiving 4-8 cycles of NAC from 2009 to 2018. Clinicopathological characteristics, NLR at pre-, mid-(every two cycles of NAC) and post-treatment were collected. The primary endpoint was OS. Among the patients, 421 patients with available pre- and post-NLR were included in the survival analysis. These patients were randomly divided into a training cohort (n = 224) and a validation cohort (n = 197). Multivariate survival model was built by including all the significant prognostic factors from the univariate analysis in the training cohort, and a nomogram model was established by “R” version 3.4.3. The performance of the model was further tested in the validation cohort by the concordance index. The second endpoint was pCR. Longitudinal analysis of NLR was performed using a mixed-effects regression model to predict pCR among 176 patients who finished 8 cycles of NAC. Results: The median follow-up time was 43.2 months for 421 patients. In the training cohort, multivariate analysis revealed that ER status, clinical node stage , pCR , pre-NLR, and post-NLR (all Ps＜0.05) were independent predictors of OS. Nomogram for OS prediction was established by combining all these significant factors. The C-indexes of the nomogram were 0.764 and 0.693, respectively in the training and validation cohort. In the longitudinal analysis, patients achieved pCR experienced a reduction of NLR every 2 cycles (Coef = -0.032, std error = 0.014, P = 0.024). Conclusions: This study demonstrated the prognostic value of pre-NLR and post-NLR towards BC patients received NAC. Based on that , a novel nomogram was established to predict the 3- and 5- year OS for BC patients. And we also found patients who experienced a decline of NLR during NAC seems to be more likely to achieve pCR from chemotherapy. Routine assessment of NLR may be an easy and affordable tool for defining prognosis.