Purpose: To evaluate the possible relationships between preoperative inflammatory markers [neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR)] and cervical stromal involvement in endometrioid endometrial adenocarcinoma. Materials and Methods: Charts and pathology results of 639 women who were operated on for endometrioid endometrial adenocarcinoma between 2000 and 2013 in the present clinic were retrospectively reviewed. Demographic, laboratory, and clinical parameters were evaluated. Results: 118 women (18.4%) had cervical stromal involvement. Lymph node positivity was significantly more frequent in the cervical stromal involvement group (p < 0.001). A threshold value of 2.41 for NLR had a sensitivity of 62.7%, specificity of 60.1%, PPV of 61.1%, and NPV of 61.8% for the presence of cervical stromal involvement. In multivariate analysis, increased NLR had a significant predictive value for cervical stromal involvement (p = 0.006, OR = 2.03), although PLR remained non-significant (p = 0.77, OR = 1.08). Conclusions: The preoperative NLR assessment is a significant predictor for cervical stromal involvement in endometrioid endometrial adenocarcinoma.