HBV is a major health problem worldwide and cause acute or chronic hepatitis, which can lead to the development of extensive liver scarring (cirrhosis), liver failure, liver cancer, and death. HIV is also the leading cause of death in women of reproductive age globally. The current study was amide to assess the seroprevalence and associated risk factors of HBV and HIV co-infections among pregnant women attending antenatal care at Shahura Health Center in Alefa District, northwest Ethiopia. A cross sectional study was conducted among 384 pregnant women attending antenatal care at Shahura Health Center from January to March 2021. Simple random sampling technique was used to pick and include the study subjects in this study. A pre-tested structured questionnaire was used to collect socio-demographic characteristics and potential associated factors. HBsAg and HIV were determined using rapid screening tests. Descriptive statistics and logistic regression analysis were done to describe and analyze the data using SPSS version 21 and p-value less than 0.05 was considered statistically significant. Seroprevalence of 7% (27/384) and 1.8% (7/384) were found for HBsAg and HIV, respectively, with co-infection rate of 1.04% (4/384). Out of the risk factors considered in the present study, an injury by sharp object (Adjusted Odds Ratio (AOR)= 3.05; 95% CI: 1.16- 8.01), having multiple sexual partners (AOR =2.66; 95% CI:1.07- 6.45), contact with HIV, HBsAg infected person (AOR=3.62; 95% CI: 1.15-11.38), blood transfusion (AOR= 7.39; 95% CI: 1.69-32.26) and abortion (AOR=3.53; 95% CI:1.20- 10.37) were independent explanatory risk factors for HBV infection(p<0.05). However, in HIV infection, having multiple sexual partners (AOR=6.81; 95% CI: 1.22-38.12) was the only independent explanatory risk factor (p<0.05). The findings of this study (e.g., intermediate infection rate of HBsAg) implicates still a need for strong commitment and continuous work in prevention and control of HBsAg and HIV transmission among pregnant women in the study area. Keywords: Ethiopia, HIV, HBsAg, Pregnancy, Risk factor, Shahura town, Seroprevalence