Hepatitis B is a potentially fatal infection that affects the liver and remains a serious public health problem worldwide. Pregnant women were vulnerable group so they need special preventive practice. Aim: The present study was aimed to investigate the effect of health belief model based education on preventive behaviors of hepatitis B among pregnant women. Design: Quasi-experimental design was utilized to fulfill the aim of the study. Settings: The study was conducted at antenatal clinics in Benha university hospital. Sample: A convenient sample of 100 pregnant women who attend the previous mentioned setting. Data: were collected through an interviewing questionnaire sheet and health belief model constructs. Results: There was highly statistically significant difference (p˂0.000) in pregnant women' knowledge, health beliefs and their health behaviors to prevent hepatitis B in the intervention group compared to the control group two months after program implementation. Conclusion Educational intervention based on HBM was effective in improving pregnant women' knowledge, health beliefs and health behaviours regarding hepatitis B. Recommendations: The present study recommended increase awareness of pregnant women about hepatitis B through regular health educational program based on health belief model.