The liver is an important organ with specific functions that influence directly on the nutritional and physiological status of every person. At the presence of any illness or injury in this organ, liver cirrhosis is always its final phase. In this pathology, patients present carbohydrate utilization and storage diminishment, as well as protein and fat catabolism increase. This situation, plus a low ingest and a bad nutrient absorption, results in a high prevalence of malnutrition. Many studies prove the importance of an opportune nutritional treatment in these patients, bringing general benefits and improving their quality of life. It's important to considerate the possible nutritional risks and deficiencies that could appear in the course of the cirrhosis to take opportune actions. The nutritional assessment and treatment is transcendental both in compensated phase (without complications) and in decompensated phase (with complications) of the illness.