Objective: To explore the trend of blood pressure among children and adolescents and its correlation with pubertal development and nutritional status, so as to provide a scientific basis for developing prevention strategies targeting early stage hypertension. Methods: In September 2023, a multi stage random cluster sampling was used to select 20 241 primary and secondary school students aged 7-18 years from 57 schools in Jinzhong, whose height, weight, and blood pressure were measured. The Chi square test for trend was used to analyze the change trend in the detection rate of elevated blood pressure and hypertension in children and adolescents with the development of adolescence puberty, and the Logistic regression was used to analyze the correlation between elevated blood pressure and hypertension and nutritional status. Results: The prevalence of elevated blood pressure was 17.3% among children and adolescents. The middle and late pubertal groups had the highest prevalence (23.2% and 24.3%), followed by the early pubertal group (19.5%) and the prepuberty group (10.8%) ( χ 2 trend =372.86， P <0.01). The prevalence of hypertension was 14.8%, with the highest prevalence reported in the late pubertal group (22.4%), followed by the middle pubertal group (18.9%), and the early pubertal (13.0%)/prepuberty (12.2%) groups ( χ 2 trend =175.43， P <0.01). The prevalence of elevated blood pressure and hypertension increased with pubertal development, regardless of gender, region, or nutritional status ( χ 2 trend =9.21-771.90, P <0.01). Overweight and obesity were influencing factors of elevated blood pressure and hypertension among children and adolescents during all stages of pubertal development ( OR =1.2-2.8， P <0.01). Conclusion The prevalence of elevated blood pressure and hypertension among children and adolescents during pubertal development is high, showing an increasing trend with pubertal development.