Treatment of low 25-hydroxyvitamin D in children includes medication, proper diet, and outdoor activities. Clinically, 25-hydroxyvitamin D is often measured in the blood to reflect the nutritional status of vitamin D. Children should have a 25-hydroxyvitamin D level greater than 20 ng/mL. Children’s 25-hydroxyvitamin D level should be more than 20ng/mL. 1. Drug supplementation: According to the “Chinese Children’s Vitamin D Nutrition-related Clinical Problems Practice Guidelines”, it is recommended to supplement vitamin D as early as possible after birth with 400-800 IU per day, and it is emphasized that vitamin D needs to be supplemented from infancy to puberty. 25-Hydroxyvitamin D level of children who have already had low vitamin D needs to be adjusted in accordance with specific levels of the dose of the drug according to the doctor’s instructions. 2. Reasonable diet: Vitamin D deficiency will lead to calcium and phosphorus metabolism disorders in children’s bodies, which will lead to growth restriction and rickets in serious cases, so it is important to pay attention to more calcium-rich foods in the diet, and for children, enough milk and dairy products, beans, fresh vegetables and fruits are all good sources of calcium. 3. Outdoor activities: Sunlight can promote the synthesis of vitamin D in human skin, so sufficient outdoor activities are conducive to improving vitamin D deficiency. Children with low 25-hydroxyvitamin D are advised to seek prompt medical attention and active treatment.