Background: Pregnancy is a unique period during a woman’s life and is characterized by complex physiological changes, which may adversely affect oral health. Objectives: The current study aimed at determining pregnant women’s knowledge, attitude and practice on oral health in 2018 to improve their knowledge, attitude and practice and subsequently decreasing oral diseases. Methods: In a cross- sectional study, 320 pregnant women referring to Ilam city health centers were selected through simple random sampling method. Data collection was done employing a questionnaire containing four main parts viz demographic, knowledge, attitude, and practice questions on oral health. Results: The mean age of pregnant women was 27.74 years. Their knowledge, attitude, and practice on oral health during pregnancy were moderate. Further, 16.7%, 12.5%, and 18.1% of them were having good knowledge, attitude and practice on oral health, respectively. The statistically significant relationship was seen between mothers’ knowledge and occupation, education, insurance coverage, and training provided in health centers on oral health (P < 0.05). The practice of pregnant mothers on oral health showed a significant relationship with their education at 0.05 level. Conclusions: Based on the finding obtained, the knowledge, attitude, and practice of pregnant women on oral health during pregnancy were almost good. Paying much more attention through proper educational interventions on oral health during pregnancy is highly recommended.