OBJECTIVES：Nowadays the vertical transmission rate of hepatitis B virus (HBV) decreases significantly in HBsAg positive mothers after newborns receive immunization. But vertical transmission of HBV may still occur in 5-10% in HBsAg and HBeAg positive mothers. This study aims at evaluating the risk of breastfeeding newborns by HBsAg and HBeAg positive mothers in mother-to-child transmission (MTCT). METHODS: Seven electronic databases and three clinical trial registry platforms were searched and the deadline was December 2019. Cohort studies evaluating the risk of breastfeeding in HBsAg and HBeAg positive mothers were included by two reviewers. The Newcastle-Ottawa was applied to assessing the risk of bias. The outcomes were analyzed by Review Manager 5.3 software and expressed as relative risk (RR) or mean difference (MD) with 95% confidence interval (CI). Heterogeneity was assessed with I-squared (I2) statistics. RESULTS: 17 cohort studies involving 2256 newborns were included in the meta-analysis. Compared to formula milk group, the number of HBsAg positive newborns increased significantly in breast milk group [RR=1.46, 95%CI (1.11, 1.92), P=0.007]. When the HBV-DNA<103 in breast milk, there was no difference in the number of HBsAg positive newborns between formula milk group and breast milk group [RR=3.62, 95%CI (1.00, 13.07), P=0.05]. When the HBV-DNA>103 in breast milk, the number of HBsAg positive newborns increased significantly in breast milk group compared to formula milk group [RR=2.69, 95%CI (1.09, 6.61), P=0.003]. Meanwhile, there was no difference in the number of anti-HBs positive newborns between formula milk group and breast milk group [RR=0.93, 95%CI (0.86, 1.01), P=0.10]. CONCLUSIONS: From the extrapolation of the existing literature, despite newborns received immunoprophylaxis, the risk of breastfeeding newborns by HBsAg and HBeAg positive mothers was still higher than formula feeding.