Background <p>Oral health education provides schoolchildren with correct information about health and oral health care techniques. Traditional oral health education has poor knowledge transmission effect. Virtual reality (VR) currently has extensive applications and excellent results in medical education and technical learning. However, its application in oral health education for primary school students has not yet been known.</p> Methods <p>A convenience sampling approach was employed to recruit 1,416 children in grades 3–5 from 16 districts of Tianjin City who had previously received traditional oral health education. One week prior to the intervention, parents received a quick response code to access the VR experience and were instructed to guide their children through the smartphone-based learning module. Then, medical staff administered questionnaires to the students in the classroom. VR efficacy was assessed by comparing oral health knowledge, attitudes, and technology acceptance between students exposed to VR and controls. Data were analyzed using Kruskal-Wallis H-tests and Mann-Whitney U-tests, and multiple linear regression analysis was employed to elucidate the pivotal factors influencing the efficacy of the oral VR experience.</p> Result <p>Children in grades 3–5 in Tianjin exhibited high receptivity to mobile-based VR technology, with a perceived ease of use of 9.03 ± 1.36 and a perceived usefulness of 9.40 ± 0.98. Among the students who experienced oral VR, 398 individuals (75%) reported a significant improvement in their attitudes towards oral health care, while 120 (22.6%) perceived a more substantial improvement. Students who experienced oral VR demonstrates a significant improvement in oral health knowledge (experimental group: 13.00(12.00,13.00) vs. control group: 10.00(8.00,12.00), <i>p</i> &lt; 0.001). Schoolchildren in grade 4, with high father educational level, good brushing habits, and prior VR experience, achieved higher oral knowledge scores after the VR experience, with statistically significant differences observed.</p> Conclusion <p>We present the first application of mobile virtual reality for oral health education in primary schools. Our study demonstrates high student acceptance of VR technology in Tianjin, China, alongside significant improvements in oral health knowledge and attitudes. Given its efficacy, accessibility, and visualization capabilities, mobile VR represents a promising tool for scalable oral health education.</p> Trial registration <p>International Standard Registered Clinical/Social Study Number Registry ISRCTN13464089(17/07/2025) “Retrospectively registered”.</p>