Cirrhosis develops from various chronic liver diseases and is a common end-stage chronic liver disease. Currently, with aggressive etiologic therapy (e.g., antiviral and alcohol cessation) and anti-fibrotic therapy, the disease can be controlled in most patients, with some of them having reversed disease and reduced liver fibrosis. To further improve clinical outcomes, the medical community has begun to pay attention to the nutritional problems of cirrhotic patients, as malnutrition is often present in cirrhotic patients and is important for their prognosis. Why do patients with cirrhosis become malnourished? It is related to the site and characteristics of the disease. The liver is the largest metabolic organ in the body where many nutrients are synthesized and metabolized, such as proteins, sugars and fats, and many vitamins. When the liver becomes diseased, the liver’s ability to synthesize and metabolize nutrients is diminished and malnutrition occurs. In addition, inadequate dietary intake due to early satiety caused by large amounts of ascites, bloating after eating and decreased appetite due to low salt and low protein diet, digestion and absorption disorders caused by abnormal secretion of bile and pancreatic juice and intestinal bacterial overgrowth, as well as disorders of nutrient metabolism and decreased function of the liver in storing nutrients can cause or aggravate malnutrition. The above reasons are superimposed, so that we often see very thin patients with advanced cirrhosis. In the early stage of cirrhosis, also known as compensated cirrhosis, although patients do not show significant wasting, they may also be at risk of malnutrition due to a short-term reduction in eating or weight loss. Malnutrition should be listed as an important complication of cirrhosis like ruptured esophagogastric fundic vein bleeding, ascites and hepatic encephalopathy. Foreign studies have found that 30% of patients with compensated cirrhosis are at risk of malnutrition, while the prevalence of malnutrition in patients in the decompensated phase is as high as 60-80% We have recently conducted a survey of patients with cirrhosis and nutritional status. After analyzing the clinical data of 150 patients already collected, 48 patients were found to be malnourished and 13 of them had a body mass index less than 18, which is in the category of wasting. Among these malnourished cirrhotic patients, three have died and three have developed liver cancer. Malnutrition can reduce the organism function, endocrine disorder and immune resistance to disease, which increases the risk of complications such as ruptured esophagogastric vein bleeding, hepatic encephalopathy, ascites and hepatorenal syndrome in patients with cirrhosis and affects survival and mortality after liver transplantation, and is an independent predictor of patient survival. Therefore, it is important to pay attention to the nutrition of patients with cirrhosis, to assess the nutritional status of patients in a timely manner, to detect malnutrition and to provide nutritional support for the prognosis of the disease. However, patients with cirrhosis and clinicians do not pay enough attention to nutritional problems, and only start to pay attention when patients are wasting. Malnutrition in patients with cirrhosis is manifested in many ways. If protein-rich meat and vegetables are not eaten enough, the prealbumin and albumin content of liver function indicators will drop. Chronic deficiency of albumin can cause the failure of various body systems, organs and tissues and aggravate cirrhosis. In recent years, vitamin D deficiency has been found to be a common problem in chronic liver disease, with a prevalence of 64%-92%, and is closely related to the severity of the disease. For example, vitamin D deficiency is associated with sustained virologic response and the degree of liver fibrosis in patients with hepatitis C. Vitamin D deficiency is also present in patients with fatty liver; and it is most common in patients with primary biliary cirrhosis. The vast majority of the 150 patients with cirrhosis we evaluated had vitamin D levels well below normal values. Vitamin D deficiency in patients with cirrhosis can lead to the development of associated bone disease, with patients developing osteoporosis, bone pain and even fractures in the later stages of the disease. In addition, deficiencies of vitamins A, B, folic acid and some trace elements are not uncommon in patients with cirrhosis. In fact, the wasting in patients with cirrhosis is not all about malnutrition; patients with combined diabetes, tuberculosis, thyroid disease or even advanced tumors can be wasted. The decrease in serum albumin content may also be the result of a large loss of urinary protein in associated nephropathy. Therefore, careful clinical differentiation is required. Since malnutrition in patients with cirrhosis is not easily diagnosed in the early stages of the disease and is easily missed in the later stages due to the presence of ascites, self-monitoring, early detection and timely correction of malnutrition are particularly important. What patients can do on their own is to record changes in body weight and calculate body mass index (BMI) by a formula: BMI = weight in kilograms/height in meters.2 If BMI is less than 18, it indicates the risk of malnutrition, which is the easiest assessment method for patients to self-monitor and detect nutritional changes at any time. Of course, it is not enough to assess the nutritional status only by BMI, the nutritional evaluation should include not only the screening of nutritional risk, but also some anthropometric contents, such as upper arm circumference, triceps skinfold thickness and hand grip strength and some biochemical test results, through which the doctor will make a comprehensive nutritional assessment and the dietitian will calculate the daily required nutritional energy to achieve individualized treatment. Patients should also pay attention to weight changes and eating changes in a timely manner, and insist on dietary supplements as long as they can eat. However, the daily diet of patients with cirrhosis is often not able to maintain metabolic needs and should be appropriately increased and supplemented to achieve nutritional balance as much as possible. Patients without hepatic encephalopathy should consume adequate amounts of protein. To prevent the occurrence of diarrhea or bloating, probiotics and soluble dietary fiber should be taken appropriately to improve the absorption of nutrients in the intestine by improving intestinal nutrition and balancing intestinal flora. The fasting period from bedtime to early morning in cirrhotic patients is equivalent to three days of starvation in normal people, so the European Society for Parenteral Nutrition recommends extra meals before bedtime for cirrhotic patients with poor nutrition, and patients with abnormal glucose metabolism can adjust the type and quantity of extra meals before bedtime according to the fasting blood sugar level in the early morning, and long-term adherence will improve the nutritional status. For patients with vitamin D deficiency, vitamin D supplementation is recommended so as to reduce the incidence of hepatic bone disease. For other deficient nutrients, appropriate supplementation should also be made. In summary, it is evident that nutritional therapy is an important part of the comprehensive treatment of cirrhosis and is an increasingly important issue for clinicians. For outpatients with milder disease, it is important to do self-monitoring, correct abnormal weight in a timely manner, detect the risk of malnutrition or pre-existing malnutrition as early as possible, and at the same time develop a suitable nutritional supplementation program with the help of physicians to maximize the benefit from it.