Oral and dental health education is an effective method to prevent oral and dental diseases in pregnant women. Objectives: To evaluate the effect of an educational intervention based on the health belief model (HBM) and assess oral and dental health behavior among pregnant women visiting Obstetrics and Gynecology Outpatient Clinic, Zagazig University Hospitals in 2021. Method: A 6-month interventional study was conducted on pregnant women receiving antenatal care at Obstetrics and Gynecology Outpatient clinic, Zagazig University Hospitals. Data collection was conducted in two phases: In the first phase, data were collected by administrating an interview questionnaire containing questions about HBM constructs. Following data collection, the teaching intervention was implemented. The second phase started three months after the completion of the intervention, and the data was recollected from both control and interventional groups. Results: A total sample of 100 pregnant women were included in the current study with a mean age of 27.78 (± 5.7) years in the interventional group and 27.29 (± 5.6) years in the control group. After the teaching intervention, there was a statistically significant difference between the two groups in all HBM constructs. Before and after the intervention, there was a significant difference between the mean value of all the variables in the interventional group. Conclusion: providing HBM-based education as a teaching intervention positively affects the oral health behavior of pregnant women in the interventional group after the intervention.