BACKGROUND Some studies investigated the prognostic role of several blood biomarkers, including the neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), lymphocyte/monocyte ratio (LMR) and Glasgow prognostic score (GPS), in osteosarcoma, but their results were inconsistent with each other. AIM To identify the prognostic value of NLR, PLR, LMR and GPS in osteosarcoma patients through reviewing relevant studies. METHODS The PubMed, EMBASE, Web of Science and CNKI databases were searched up to October 2, 2021. The primary and second outcomes were overall survival (OS) and disease-free survival (DFS), respectively. The hazard ratios (HRs) with 95% confidence intervals (CIs) were combined to assess the association between these indicators and prognosis of osteosarcoma patients. RESULTS A total of 13 studies involving 2087 patients were eventually included. The pooled results demonstrated that higher NLR and GPS were significantly associated with poorer OS (HR = 1.88, 95%CI: 1.38-2.55, P < 0.001; HR = 2.19, 95%CI: 1.64-2.94, P < 0.001) and DFS (HR = 1.67, 95%CI: 1.37-2.04, P < 0.001; HR = 2.50, 95%CI: 1.39-4.48, P < 0.001). However, no significant relationship of PLR and LMR and OS ( P = 0.085; P = 0.338) and DFS ( P = 0.396; P = 0.124) was observed. CONCLUSION Higher NLR and GPS were related with worse prognosis and might serve as novel prognostic indicators for osteosarcoma patients.