Diarrhea in children refers to diarrheal disease, which is a common and frequent disease in children, mostly occurring in infants and children under 3 years of age, with a high incidence from 6 months to 2 years of age, and is one of the main causes of malnutrition and impaired growth and development in children, to which parents need to pay attention. The two main causes of diarrhea are infectious and non-infectious. Non-infectious diarrhea mainly includes lactose intolerance, protein allergy, catching cold and other causes. Infectious diarrhea includes diarrhea caused by various viruses, bacteria and other microbial infections, and can also be some infectious diseases such as norovirus, cholera and other serious infectious diseases. The principles of treatment for pediatric diarrhea are to maintain nutrition with a reasonable diet; rapidly correct disorders of water and electrolyte balance; control infections inside and outside the intestinal tract; enhance care and prevent complications with symptomatic treatment; and avoid abuse of antibiotics. If your child has severe diarrhea, accompanied by symptoms such as less urine and dry skin, you should pay more attention to it and need to replenish water and electrolytes in time. You can prepare oral rehydration salts at home and take 1 packet with 500ml of water as required to replenish water and electrolytes quickly to avoid circulatory failure and life-threatening, and then go to the doctor as soon as possible.