According to the World Health Organization, the normal values of hemoglobin, or hematocrit, are as follows: 110 g/L for children aged 6 months to 5 years, 115 g/L for those aged 5-11 years, and 120 g/L is normal for children older than 12 years, including 12 years of age, just like adults. According to the pediatric age group, the normal value of hemoglobin is 110g/L for children between the ages of 1-3 years, and for infants under 6 months of age and newborns, there are age-specific standards because they have different physiological characteristics. There are many factors that affect the results of hemoglobin test, such as the location of blood collection, altitude of the living area, the presence of dehydration and rehydration, and the absence of infection, etc. Only a comprehensive assessment of the influencing factors can make an accurate judgment on whether the hemoglobin test results are normal.