Background: The preoperative C-reactive protein/Albumin ratio (CAR) is valuable for predicting the prognosis of patients with various types of cancers. The aim of the present study is to investigate the prognostic value of the preoperative CAR and compare it with other systemic inflammatory response markers in patients with soft tissue sarcoma (STS). Methods: This retrospective study included 206 patients with STS. The optimal cutoff value of the CAR was determined by receiver operating characteristic (ROC) analysis. The impact of the CAR and other clinicopathological features on overall survival (OS) and disease-free survival (DFS) was evaluated using univariate and multivariate Cox regression analyses. Kaplan-Meier survival analyses were used to compare groups classified by the CAR. Additionally, the area under the receiver operating characteristic curve (AUC) was used to compare the predictive ability of the CAR, high-sensitivity modified Glasgow prognostic score (Hs-mGPS), neutrophillymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR). Results: The optimal cut-off value of the CAR was 0.1035 according to the ROC analysis. An increased CAR (>= 0.1035) was significantly associated with older age, larger tumor size, deep tumor location, higher tumor grade and more advanced American Joint Committee on Cancer (AJCC) stage (all P< 0.05). Patients with an elevated CAR (= 0.1035) exhibited a shorter median survival time and lower 5-year OS rate than those with a CAR< 0.1035 (68.2 vs 115.8 months, P = 0.000; 44.6% vs 80.9%, P = 0.000, respectively). The results of a multivariate analysis indicated that the CAR (Hazard ratio (HR) 2.47, 95% confidence interval (CI) 1.47-4.14, P = 0.001) was an independent prognostic factor for OS along with tumor grade (P< 0.05). Additionally, the CAR exhibited a greater AUC value (0.662) than the NLR and PLR, but the value was equal to the Hs-mGPS. Conclusions: The preoperative CAR is an independent prognostic factor predicting prognosis in STS and exhibits superior prognostic ability compared to the established inflammation-based prognostic indices.