BACKGROUND: Internal jugular vein (IJV) and subclavian vein (SCV) have been the most preferred central venous catheterization (CVC) sites clinically. Based on individual preference and institutional routine, however, the choice of IJV catheterization (IJVC) or SCV catheterization (SCVC) is lack of high-level evidence. We sought to provide useful clinical strategy by comparing the catheterization time, success rate and the mechanical complications involved of the two CVCs.METHODS: We systematically reviewed eligible studies from PubMed, OVID, Cochrane and ClinicalTrials.gov till February 2020. The primary outcomes were catheterization time and overall success rate, and the secondary outcomes were the first-attempt success rate and the instant mechanical complications. RESULTS: A total of 3378 patients from 7 studies were included in the analysis. Neither difference was found on the catheterization time (SMD 95% CI: -0.095-0.124, p=0.792), nor any difference on the overall success rate (RR=1.017, 95% CI: 0.927-1.117, p=0.721, I2=89.6%) between the 2 procedures. However, subgroup analysis showed overall success rate of IJVC was significantly lower than that of SCVC (RR=0.906, 95%CI:0.850-0.965, p=0.002) in adult patients. The first-attempt success rate of IJVC group was higher than SCVC group in the adult patients (RR=1.472, 95%CI:1.004-2.156, p=0.047). No significance was detected in arterial injury (RR=1.137, 95% CI: 0.541-2.387, p=0.735) and pneumothorax (RR=0.600, 95% CI: 0.32-1.126, p=0.112) between the two procedures. Hematoma was significantly more in IJVC group than that in SCVC group (RR=2.824, 95% CI: 1.181-6.751, p=0.02). CONCLUSIONS: Compared with IJVC, SCVC has a higher overall success rate while a lower first-attempt success rate in adults, and has involved with less hematoma. However, more high-quality studies are essential to provide better evidence especially in pediatric patients. TRIAL REGISTRATION: This meta-analysis was pre-registered in PROSPERO (CRD42020165444).