The lymphocyte-to-monocyte ratio (LMR), as a surrogate marker of systemic inflammation, has been found to be a novel prognostic indicator in various malignancies. Data from 672 advanced epithelial ovarian cancer (EOC) patients treated with neoadjuvant chemotherapy (NAC) followed by debulking surgery were analyzed, and the prognostic value of LMR were evaluated. The optimal cutoff point of LMR in prediction of survival was defined as 3.45 through receiver operating characteristics curve analysis. Patients with low LMR (<= 3.45) at diagnosis tended to have more adverse clinical features, such as higher histological grade, chemotherapy resistance, and residual tumor > 1cm after debulking surgery. No significant correlation was found between LMR level and age and histological type. Moreover, after NAC, the complete remission (CR) rate for the low-LMR group was lower than those for the high-LMR group (P<0.05). Patients with low LMR had poorer progression-free survival (PFS; P<0.001) and overall survival (OS; P<0.001). Multivariate analysis revealed that low LMR was an independent adverse predictor for PFS and OS. Results indicated that low LMR at diagnosis is a novel independent prognostic factor for advanced EOC. However, prospective study is needed to validate this prognostic factor and biological studies should further investigate the mechanisms underlying the correlation between low LMR and poor prognosis in advanced EOC.