Patients with AIDS, especially in advanced stages, are likely to have a common symptom of persistent diarrhea, usually lasting for more than one month, with diarrhea occurring three or more times a day, especially in patients who are not on effective antiretroviral therapy. If this is the case, patients are advised to start antiviral treatment as soon as possible. After regular antiviral treatment, the patient’s diarrhea symptoms can be gradually relieved, which can also reflect the effectiveness of antiviral treatment. If the patient has already undergone antiviral treatment and has diarrhea, it is also necessary to be alert to the presence of intestinal infections, bacterial infections, viral infections and mycobacterial infections are more common. After effective treatment, the patient’s symptoms can be relieved. During the period of diarrhea, patients can be given appropriate amount of rehydration, and can be treated symptomatically with drugs to regulate intestinal flora.