Simple, non-aversive methods to identify cervical neoplasia are needed. The purpose of this study was to investigate the clinical value of differential white blood cell (WBC) counts as a biomarker for cervical neoplasia. We performed a retrospective review of laboratory results in 407 cervical cancers, 495 cervical intraepithelial neoplasias (CIN) and 916 healthy controls. Because pretreatment neutrophil and monocyte counts showed the potential as a biomarker, we combined these parameters and designated this combined marker MNM (multiplication of neutrophil and monocyte counts). MNM showed a sensitivity of 53.1% and a specificity of 78.1%, which are much higher than those of SCC-Ag. On Cox multivariate analysis, MNM positivity (hazard ratio = 2.82, p = 0.042), stage and tumour size were independent predictors of poor prognosis. Our findings suggest that pretreatment MNM could be a candidate as a simple and cost-effective biomarker in cervical cancer.