Occlusive gangrene of the lower limbs belongs to the more serious cases, and it is difficult to estimate the specific survival period of occlusive gangrene of the lower limbs without amputation; if proper care is taken, the survival time may be prolonged appropriately, and may reach several years or even longer; if improper care is taken and persistent infection occurs, the survival period may be shortened, and the survival period may be from 1 month to several months. Occlusive gangrene of the lower limbs belongs to a kind of gangrene, which refers to the special morphological changes such as black, dark green, etc. that occur after necrosis of tissues due to infection by putrefactive bacteria, the causes of which include arteriosclerosis occlusive disease of the lower limbs, thromboembolic vasculitis and diabetic foot. The survival time of lower limb occlusive gangrene without amputation varies significantly, generally from person to person. If the patient has mild symptoms and is properly cared for, survival may be appropriately prolonged, up to several years or more. If the symptoms are more severe and persistent infection occurs, it may lead to severe sepsis, septicemia, bacteremia and other diseases, and the survival time may vary from one month to several months, which has a greater impact on the life and health of the patient.