BACKGROUND Viral hepatitis is a serious blood-borne and sexually transmitted systemic communicable disease affecting the liver. Commonly, it is caused by hepatitis B and C viruses. HIV infection has been one of the largest public health challenges that can also be transmitted vertically. OBJECTIVE To determine seroepidemiological patterns and predictors of hepatitis B, C and HIV viruses among pregnant women attending antenatal care clinic at Atat Hospital, Southern Ethiopia. METHODS Hospital-based cross-sectional study was conducted among 222 pregnant women from May to July, 2017. A structured questionnaire was used to collect socio-demographic characteristics and predicators of hepatitis B, C and HIV infections through face-to-face interview. Venous blood sample of 5 mL was collected from study participants, and serum was tested for HBsAg, anti-HCV and anti-HIV using rapid test kits and further confirmed by enzyme-linked immunosorbent assay. Logistic regression analysis was used to identify predictors of hepatitis and HIV infections. A p-value less than 0.05 was considered statistically significant. RESULTS The overall seroprevalence of hepatitis B, C and HIV infections were 4.5%, 1.8% and 2.7%, respectively. In multivariate analysis, the prevalence of hepatitis B virus infections was significantly higher among patients having history of poly-sexual practices (adjusted odds ratio = 11.31; 95% confidence interval = 1.24-28.69, p = 0.003), history of abortion (adjusted odds ratio = 8.64; 95% confidence interval = 5.5-30.36, p = 0.034), home delivery by traditional birth attendants (adjusted odds ratio = 9.06; 95% confidence interval = 2.01-13.36, p = 0.005) and blood transfusion (adjusted odds ratio = 18.1; 95% confidence interval = 2.63-114.24, p = 0.001). HIV co-infection was present in 40% and 100% of hepatitis B virus and hepatitis C virus positive pregnant women, respectively. All hepatitis C virus positive women had a history of ear piercing, abortion and home delivery. CONCLUSIONS Hepatitis B, C and HIV were all uncommon infections in this population, with hepatitis B virus the most common. All hepatitis C virus positive pregnant women were co-infected with HIV. Significant association was found between hepatitis B virus infection and predictors. Therefore, continuous screening of pregnant women for hepatitis B and C infections should be performed.