Sarcopenia is a common complication in the elderly that increases the risk of falls fractures and other chronic diseases. Nutritional treatments are one of the most common means of alleviating and preventing sarcopenia in the elderly with favourable results in clinical patients and patients treated at home which have the advantages of high operability effective and low side effects. Taking the updated post - 2018 diagnostic criteria for sarcopenia such as EWGSOP2 AWGS2019 and IWGS as a reference this paper is based on various types of population-based studies carried out in national and international research including various types of studies published in recent years such as multiple randomized controlled clinical trials systematic reviews or meta-analyses cohort studies and cross-sectional studies. We summaries the possible pathogenesis of sarcopenia together with the screening diagnosis assessment prevention and nutritional treatment of sarcopenia. For clinical diagnosis and nutritional intervention of sarcopenia in the elderly the grading of evidence and strength of recommendation criteria in the guidelines are based on the European Society of Cardiology criteria. Nutritional treatment recommendations are made for different types pathogenesis disease severity and other characteristics which provides references for the normation and standardisation of clinical diagnosis and treatment.