Background The prognostic role of CRP (C-reactive protein) in gynecological tumors has been previously reported in individual studies, but whether CRP can be used as a separate potential prognostic factor has not been systematically reviewed. The purpose of this research is to determine if there is a link between CRP levels and the prognosis of gynecological cancer patients. Methods A systematic search was carried out to find the literature evaluating the predictive role of CRP in the prognosis of gynecological cancer patients. For the purpose of determining the relationship between CRP and clinicopathological characteristics, the pooled odds ratio (OR) was calculated. A hazard ratio (HR) with a 95% confidence interval (CI) was used to determine differences in overall survival (OS), disease-free survival (DFS), or progression-free survival (PFS) between patients with low and high CRP levels. Results A total of 19 studies, including 4062 patients, were analyzed retrospectively. The FIGO stage was related to the CRP level (OR = 0.43, 95% CI: 0.19–1.00). Age, lymph node metastasis, and histological grade were not associated with CRP level (OR = 0.93, 95% CI: 0.69–1.25; OR = 0.91, 95% CI: 0.65–1.28; OR = 0.74, 95% CI: 0.52–1.05). Worse OS (HR = 1.40, 95% CI: 1.23–1.57), DFS (HR = 1.20, 95% CI: 1.12–1.28), and PFS (HR = 1.57, 95%CI: 1.23–1.91) were associated with elevated CRP levels, as shown by the pooled results. Subgroup analysis was performed according to cancer type (endometrial cancer: HR = 1.15, 95% CI: 1.02–1.28; ovarian cancer: HR = 1.67, 95% CI: 1.03–2.31; cervical cancer: HR = 1.42, 95% CI: 1.19–1.64), multivariate value (HR = 1.22, 95% CI: 1.10–1.33), and age (HR = 1.50, 95% CI: 1.28–1.72). Significant correlations were observed between CRP and OS. Conclusions CRP may be utilized as a prognostic indicator for a variety of gynecologic malignancies, including cervical cancer, ovarian cancer, endometrial cancer, and vulvar cancer.