Factors affecting the growth and development of children include internal and external factors. The former refers to heredity, gender and the physical condition of the mother during pregnancy, while the latter refers to nutrition, living environment, study, exercise and disease after birth. (1) Heredity: The offspring’s skin, hair color, facial features, body height, and early and late sexual maturity are all related to the heredity of both parents. (2) Sex: Except for early adolescence, males are slightly larger than females. (3) Pregnant mother’s condition: the living environment, nutrition, illness, emotion and medication during pregnancy of the pregnant mother have certain influence on the child. (4) Nutrition: reasonable and adequate nutrition after birth is the material basis for growth and development, and has a great impact on weight, especially breastfeeding during infancy. (5) living environment: including living conditions, sunlight, air, water, soil and other conditions. (6) exercise and learning: including the system of life, care, education, and physical exercise, learning, etc., is the main factor to promote growth and development and cope with accidents. (7) disease: especially endocrine diseases and some chronic diseases. Such as: hypothyroidism and tuberculosis, etc. After understanding the law of growth and development of children and its influencing factors, we should create favorable conditions and prevent undesirable factors to ensure and promote the physical growth and intellectual development of children, we should know that the physical growth can be promoted, the child’s character can be shaped by this law. At the same time, we can judge the growth and development of children according to the normal growth law, and find out the deviations and deficiencies in time to correct and intervene. We often use the triangle to suggest a person’s development, the base is the genetic factors, the principle is not changeable. On one side is the environment, and on the other side is learning and exercise, which are variable factors that can affect the area of the triangle.