In recent years, for the clinical implementation of nutritional support treatment for critically ill patients, international guidelines developed by the American Critical Care Association (SCCM), the American Association for Parenteral and Enteral Nutrition (ASPEN, 2016), and the European Association for Parenteral and Enteral Nutrition (ESPEN, 2018) have issued clear recommendations. However, patients with critical respiratory illness have their own particularities in disease metabolism and treatment modes, and there is no unified consensus and guideline recommendation on nutritional support treatment strategies for critical respiratory illness. With the rapid development of clinical nutrition, there are increasing researches at home and abroad on whether patients with critical respiratory illness can improve survival rate, shorten ICU stay and improve patients' quality of life through nutritional support therapy. In order to standardize the nutritional support treatment of respiratory critical patients, domestic respiratory critical care and nutrition experts systematically retrieved, screened and evaluated relevant evidence-based medical evidence, including high-quality systematic review, meta-analysis and related RCT studies. Multiple rounds of discussion were conducted on 22 issues that medical staff paid most attention to during the implementation of nutritional support treatment for respiratory critical patients, and 24 recommendations were finally determined by expert voting and scoring.