To analyze the time-varying characteristics of weight among Han primary and secondary school students in Xinjiang from 1985 to 2019, so as to provide a scientific basis for formulating nutrition policies for adolescents in ethnic minority areas.

Weight data of Han primary and secondary school students aged 7-18 in Xinjiang from the National Student Physical Fitness and Health Survey from 1985 to 2019 were selected. Statistical analysis was conducted by using general linear model test, one-way ANOVA and t-test. The weight development trends in 2025 and 2030 were predicted through time-series analysis.

From 1985 to 2019, the weight of Han Chinese boys and girls from primary and secondary schools in Xinjiang showed a continuous upward trend (boys: B=0.25, girls: B=0.16, P < 0.01). There were statistically significant differences in weight between boys and girls aged 7-18 in different years (boys: F=102.35-142.05, girls: F=98.03-140.59, P < 0.01). Compared with 1985, the weight of urban boys and girls increased by 11.92 and 7.95 kg in 2019, as well as rural boys and girls by 11.36 and 5.61 kg, and the average weight gain of urban students was greater than that of rural students. From 1985 to 2019, the weight of urban boys and girls were higher than that of rural boys and girls (boys: t=30.12-37.55, girls: t=30.12-38.64, P < 0.01). In 2005, the weight difference between urban and rural boys and girls was the largest, at 4.23 and 2.32 kg. The average weight of boys and girls in the age groups of 7-18 would continue to increase in 2025 and 2030; compared with 2019, the 7-year-old age group for boys and the 17-year-old age group for girls would have the largest growth in 2030 by 2.29 and 3.75 kg.

From 1985 to 2019, the weight of students aged 7-18 in Xinjiang showed an upward trend, and the weights of both boys and girls would gradually increase in 2025 and 2030. Attention should be paid to students' physical health and adopt comprehensive measures to prevente overweight and obesity.