Objective: Evaluation of mean platelet volume (MPV), neutrophil to lymphocyte ratio (NLR), and platelet count in the detection of malignant and benign ovarian tumors. Material and Methods: Sixty-six patients admitted to the present clinic over three years were included in the study. Patients diagnosed with ovarian cancer were grouped into the areas of epithelial and granulosa cell tumor diagnosis. The values were compared to patients with benign cystic structure. Patients' preoperative hematologic parameters and their values four weeks postoperatively were analyzed. Statistical analyses were performed with SPSS software. Results: MPV, NLR, and platelet count were observed at a higher rate as statistically significant in patients diagnosed with malignant ovarian cancer, compared to those with benign adnexal mass. Conclusion: The hematological parameters such as MPV, NLR, and platelet count in the detection of malignant ovarian tumors have been evaluated as useful new markers.