Previous studies explored the prognostic value of pretreatment platelet count, fibrinogen, and d-dimer level in patients with several types of cancer, however, a comprehensive conclusion has not been reached in osteosarcoma patients. PubMed, Web of Science, Embase, and CNKI databases were systematically searched for eligible studies up to May 09, 2023, and pooled hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were calculated to assess the prognostic impact of these indicators in osteosarcoma patients. Twelve studies from China consisting of 1682 patients were finally included. Our findings revealed that an elevated level of pretreatment platelet or d-dimer was associated with a worse outcome of overall survival (platelet: HR = 1.63, 95% CI: 1.18-2.26, P = .003; d-dimer: HR = 2.29, 95% CI: 1.58-3.31, P < .001). Based on current evidence, pretreatment platelet count and d-dimer level could be good prognostic biomarkers for Chinese osteosarcoma patients. However, future validation is also needed.