When a baby presents with diarrhea with fever, the first thing that needs to be done is to clarify the cause of the disease and must be seen in the pediatric internal medicine department for an interview, which requires routine blood and stool tests. The most common causes of diarrhea and fever in babies are infectious factors, such as bacterial or viral infections that cause fever in babies; in addition, diarrhea in infants leads to high water loss in the body and a decrease in effective blood circulation, which in turn causes fever. At the same time, the affected baby can be accompanied by more obvious symptoms of dehydration, including dryness of the baby’s skin and mucous membranes, sunken fontanelle, reduced tears and urine, or even no tears or urine. In the case of bacterial diarrhea, active anti-infective treatment is required. The main manifestation of bacterial diarrhea is mucus-like stools or mucopurulent and bloody stools. If the symptoms are not very serious, oral antibiotic treatment can be given; if the symptoms are more serious, intravenous drip antibiotic treatment is needed. If the diarrhea is caused by dehydration, most of it can be corrected by oral rehydration therapy, while severe dehydration requires intravenous rehydration. Babies with fever and diarrhea can also be treated with microecological therapy by giving intestinal probiotics or gastrointestinal mucosal protectors such as montelukast. Symptomatic treatment is also important. If the fever exceeds 38.5 degrees Celsius, oral ibuprofen can be combined with physical cooling to reduce the fever; if the fever is lower than 38.5 degrees Celsius, physical cooling can be taken. Diet should also be noted, breastfed infants continue to breastfeed, appropriately limit the number of nursing or shorten the duration of each nursing, suspend complementary foods; artificially fed children can be fed with equal amounts of rice soup or diluted milk or other milk substitutes, from rice soup, porridge, noodles, etc. gradually over to a normal diet. For lactose intolerant children, add lactase to the diet or remove lactose from the diet. During diarrhea, continue to eat and give your baby a normal diet appropriate to his or her age, and do not “fast” as much as possible, as fasting can lead to prolonged symptoms and loss of nutrition.