Background: A consensus has not yet been reached regarding the abilities of gender, age, tumor size, tumor location, histologic subtypes, and surgery in the prediction of survival in osteosarcoma. We aimed to disclose their prognostic significance by conducting a meta-analysis of all the published data from the last decade. Materials and Methods: Electronic database searches were conducted in PubMed, Embase, and Web of Science for relevant articles published within the last ten years. The pooled hazard ratio (HR) and corresponding 95% confidence interval (CI) were obtained to evaluate the prognostic values of the target factors. Results: A total of 18,126 patients from 40 studies were eventually included. Results indicated that gender (male vs. female: 1.21, 95% CI, 1.11–1.32; female vs. male: 0.85, 95% CI, 0.75–0.98), age (12–20 vs. ≤12: 1.37, 95% CI, 1.13–1.65; ≥20 vs. <20: 1.29, 95% CI, 1.08–1.55; ≥40 vs. <40: 1.63, 95% CI, 1.21–2.20; ≥50 vs. <25: 2.60, 95% CI, 1.92–3.53; ≥60 vs. <60: 1.11, 95% CI, 1.06–1.18), tumor location (non-extremities vs. extremities: 2.10, 95% CI, 1.76–2.51; proximal vs. distal femur: 3.68, 95% CI: 1.51–8.96; proximal vs. distal humerus: 3.15, 95% CI: 1.53–6.49), tumor size (≥5 vs. <5: 1.42, 95% CI, 1.09–1.86; >8 vs. ≤8: 1.55, 95% CI, 1.07–2.24; >9 vs. ≤9: 1.44, 95% CI, 1.05–1.96), chemotherapy response (poor vs. good: 2.45, 95% CI, 2.02–2.97; good vs. poor: 0.41, 95% CI, 0.34–0.48), and surgery (yes vs. no: 0.45, 95% CI, 0.36–0.57; amputation vs. salvage: 2.34, 95% CI, 1.47–3.74) were significantly associated with overall survival in osteosarcoma patients. Conclusion: The meta-analysis demonstrated that male patients, older age, large tumor size, non-extremity osteosarcoma, proximal osteosarcoma, poor chemotherapy response, no surgical treatment, and amputation surgery were correlated with a poor prognosis in osteosarcoma patients. Keywords: Prognosis, Osteosarcoma, Clinicopathology, Meta-analysis