Objective To evaluate the flushing effects of normal saline (NS) and heparin saline (HPS) after central venous catheterization. Methods We searched PubMed, EMbase, The Cochrane Library (Issue 12, 2015), CBM, CNKI, VIP and WanFang Data to collect randomized controlled trials (RCTs) on the flushing effects of NS versus HPS after central venous catheterization from inception to December 2015. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then RevMan 5.3 software was used for meta-analysis. Results A total of 12 RCTs involving 2 092 patients were included. The results of meta-analysis showed that no significant differences were found between the two groups in occlusion rate (OR=1.58, 95%CI 0.79 to 3.14,P=0.19) and the catheter days (OR=–7.24, 95%CI –22.90 to 8.41,P=0.36), while the HPS group had more advantage than the NS group in decreasing the incidence of phlebitis (OR=2.57, 95%CI 1.52 to 4.34,P=0.000 4). Subgroup analysis revealed that HPS provided more superiority over NS in lessening the occlusion rate (OR=1.85, 95%CI 1.22 to 2.80,P=0.004), no significant difference was found when comparing NS to 10 units, and 100 units HPS (10 units: OR=1.51, 95%CI 0.94 to 2.43,P=0.09; 100 units: OR=1.51, 95%CI 0.63 to 3.60,P=0.09). Conclusion HPS appears to be more beneficial than NS, larger rigorously studies are needed for better understanding on the effects of NS and HPS.