This study was conducted to determine the basic anthropometric index changes of Kinh and H'mong children in Yen Bai Province. The research was carried out on target groups that consisted of 1694 children (851 males and 843 females) aged 15 to 17. The research results show that the children' standing height, weight, average chyst size, average head size, average neck size, average left arm length, average abdomen size average buttock size and BMI increased with age. The basic anthropometric indices of Kinh children are larger than for H'mong children. According to the Pignet index. the average size of both Kinh and H'mong children is in the weak groups. The morphological-physical indexes of Kinh students have improved when compared to the Biological norms for Vietnamese people in the 1990s found in previous studies while these indicators are equal to or lower for H'mong children.