Objective: To analyze the dynamic trend of caries prevalence of permanent teeth and DMFT in the 7-year-old primary school students of Han nationality from 1991 to 2014, and to provide a basis for the development of caries prevention measures for children and adolescents. Methods: A total of 100 652 students from the 7yearold age group of 30 provinces, autonomous regions and municipalities in 1991, 1995, 2000, 2005, 2010 and 2014 from Physical Fitness And Health Surveillance Of Chinese School Students were selected. DMF% and DMFT were used as indicators to analyze the change trend of caries prevalence of permanent teeth and DMFT in different groups of 7-year-old primary school students of Han nationality in the past 25 years. Results: During the 25 years, the DMF% of primary school students in 7 years old group showed an overall U-shaped development trend. DMF% was 7.9% in 1991, lowest at 3.2% in 2005, and 5.2% in 2014. The DMFT basically showed a steady fluctuation trend. DMFT of rural girls were higher than the other three groups. Conclusion In view of the serious caries problem among primary school students aged 7 in China, it is necessary to continue to improve oral health strategies, strengthen the publicity of prevention and treatment of caries and oral health education, increase the input of oral health resources in rural areas, reduce the prevalence of caries and protect children’s oral health.