It was once a wonderful wish of parents who lived in difficult times to make their children fatter, and chubby little dolls were loved by everyone, but with the rapid development of China’s economy, people’s living standards continue to improve, fat children continue to increase, and childhood obesity is gradually becoming a serious social problem. With the rise in the incidence of childhood obesity, the incidence of childhood type 2 diabetes, childhood hypertension, childhood fatty liver and so on is getting higher and higher. So, what kind of children are obese? What should parents pay attention to in daily life? Generally speaking, if the child’s height is within the normal range, but the weight exceeds the average weight of children of the same age and sex by more than 20%, it is obesity. The causes of obesity are many and varied. In addition to the common simple obesity, there are also obesity caused by endocrine disorders and the use of drugs to treat certain diseases. Clinically, obesity is often graded: mild obesity is more than 20% of standard weight, moderate is more than 30%, and severe is more than 50% of standard weight. Or by calculating the child’s body mass index = weight (kg) / height 2 (m) to find out whether the child’s weight is overweight. If the body mass index is greater than 20 kg/m2, the child is overweight. Childhood obesity can delay the development of children’s aerobic capacity; cause insurmountable psychological behavior damage in children, make self-esteem and self-confidence suffer serious damage, and have destructive negative effects on children’s character shaping, temperament cultivation and habit formation; be an important risk factor for cardiovascular disease, diabetes and hypertension in adult life. Some obese children can occur hyperlipidemia, abnormal glucose tolerance, fatty liver, hypertension, sleep apnea, etc.. Therefore, parents should pay enough attention to children’s obesity, adjust the amount of food and activity of children in daily life according to the nutritional needs and activity capacity of children of different ages, and eat a balanced diet to avoid excessive calorie intake, resulting in children’s obesity. If the child’s daily diet is not significantly increased compared with children of the same age, and the usual activity is not less, but the child is obese, we should go to the hospital in time for the necessary examination, early detection of obesity caused by disease, and give appropriate treatment. Those children who eat a lot and have little activity do not lose weight after the adjustment of eating less and exercising more, or children who have been obese for a long time should also go to the hospital for examination in time to find out the comorbidity of obesity as early as possible and give attention and early appropriate treatment, and do not blindly reduce weight for children at home by yourself.