Abstract: Objective To explore the expression of CDK6 in early ovarian cancer and explore its clinical significance. Methods Real-time PCR and immunohistochemistry was used to examine the differential expression of CDK6 mRNA and protein in ovarian cancer and normal ovarian tissues. The correlation of CDK6 expression with the clinical characteristics and prognosis of the patients was analyzed. Results The expression of CDK6 mRNA was obviously up-regulated in 36 ovarian cancer tissues as compared to that in 16 ovarian tissues. Immunohistochemistry demonstrated that CDK6 protein was expressed in both the cytoplasm and cell nuclei. Compared with the 48 normal ovarian tissues, the 121 ovarian cancer tissues showed significantly up-regulated CDK6 protein expression (P=0.044). Increased CDK6 protein expression was not significantly correlated with the clinical features of the patients with ovarian cancer, but showed a significant negative correlation with the patients’ prognosis (P=0.006). Multivariate analysis suggested that CDK6 expression level was an independent prognostic indicator (P=0.008) for the survival of patients with ovarian cancer. Conclusion Increased CDK6 protein expression may promote the development and progression of early ovarian cancer.