Objective To investigate the correlation between vital capacity, pulmonary ventilation and morphological parameters among children living in different altitude areas, so as to provide a reference basis for the development of prevention and control strategies for high altitude illness. Methods From January 2019 to June 2020, primary and secondary school students aged 7 to 15 years old were randomly selected from three different altitude areas, which were Xining (2 260m, low altitude group), Haixi (2 900m, medium altitude group), and Yushu (4 493m, high altitude group), respectively. The vital capacity, pulmonary ventilation and morphological parameters of the selected children were recorded. Results The vital capacity, pulmonary ventilation and morphological parameters showed statistically significant difference among three groups (P<0.05). The vital capacity and pulmonary ventilation were positively correlated with lung volume, but negatively correlated with lung density and lung artery diameter (P<0.05). Logistic regression analysis showed that there were three factors affecting children's vital capacity and lung ventilation: mean lung density, total lung transverse diameter, and total lung volume (P<0.05). Conclusion The monitoring of lung morphological indexes, mean lung density, total lung transverse diameter, and total lung volume can effectively judge children's lung function, and have certain value in the prevention and treatment of related high-altitude illness.