Elderly people who don’t eat and have diarrhea may have a poor diet and need to adjust their diet; they may also have acute gastroenteritis, intestinal tumors and other diseases. Acute gastroenteritis can be treated with levofloxacin and other anti-infectives; intestinal tumors need surgical treatments, chemotherapy or radiotherapy. 1. Improper diet:Elderly people have poor intestinal function, if they consume cold and irritating food, it may lead to diarrhea, poor appetite and not eating. Diet should be adjusted to consume warm and well-digested food, such as millet porridge, pumpkin porridge, soft noodles, and avoid cold and irritating food. 2. Acute gastroenteritis:often due to bacterial infection leading to gastrointestinal inflammation, causing gastrointestinal mucosal congestion, edema, resulting in diarrhea, do not want to eat, but also abdominal pain, fever and other symptoms. Levofloxacin and ceftriaxone can be applied to fight infection, and attention should be paid to fluid rehydration and prevention of water-electrolyte balance disorders. 3. Intestinal tumor: the elderly can also be seen in intestinal tumors, such as colon cancer, rectal cancer, which often have symptoms such as change of stool properties, defecation habits, poor appetite, weight loss, anemia and so on, which can be manifested as not eating and having diarrhea. Treatment should be surgical treatment, chemotherapy or radiotherapy. If the elderly do not eat and have diarrhea, they should go to the hospital in time to find out the cause and follow the doctor’s instruction to standardize the treatment after excepting the physiological cause.