: School teachers need to have a better understanding of oral health aspects as schools serve as an effective environment for learning. Educators hold a significant position in conveying the importance they attribute to oral health in their lives. According to the World Health Organization, school teachers should include oral health promotion activities to evaluate students' oral health, track injuries, illnesses, and absenteeism related to oral health, advocate oral health prevention, and serve as role models. The aim of this study was to evaluate the conceptual understanding of oral health among primary school teachers in Riyadh, Saudi Arabia. : Data for this study were collected from 404 primary school teachers using a structured and pre-validated comprehensive measure of oral health knowledge (CMOHK) questionnaire. : The distribution of CMOHK scores indicated that 247 (61.2%) participants demonstrated good conceptual knowledge, 95 (23.5%) participants exhibited fair knowledge, and 62 (15.3%) participants were classified as having poor knowledge. The male group exhibited lower values for the CMOHK score in comparison with the female group; however, these findings were not statistically significant. The findings indicated that the group of government school teachers exhibited higher values for the dependent variable CMOHK score compared to their private school counterparts. : The average CMOHK score observed in this study is regarded as fair. It is crucial for school teachers to possess strong oral health knowledge, as they significantly influence the oral health knowledge and behaviors of children.