Objective To evaluate the nutritional status of Shanghai Xinjing community old people with MNA-SF, to analyze the relationship between nutritional status and sarcopenia, and to observe the effect of nutritional intervention. Methods 300 old people aged 65 or older were randomly selected from the community and to were divided into three groups based on the scores of MNA-SF: normal nutritional status group, risk of malnutrition group and malnutrition group. BIA was used to determine whether patients were with sarcopenia in all three groups. Malnutrition group was divided into interventional group and control group, interventional group implemented HMB for 90 days nutritional intervention. Results The prevalence rate of sarcopenia in male and female communitydwelling elders was 22.6% and 12.1% by using BIA respectively. The appendicular skeletal muscle to height squared ratio in normal nutritional status group (7.6±0.62 in males and 6.23±0.15 in females) was higher than those at risk of malnutrition group (7.15±0.83 in males and 5.84±0.26 in females) and the malnutrition group (6.42±0.54 in males and 5.46±0.68 in females). All differences were statistically significant (P<0.05). After intake of JiRou (HMB supplementation was 2.6g/d) intervention for 90 days in malnutrition people, appendicular skeletal muscle in intervention group was statistically increased than control group (P<0.05). Conclusions People with malnutrition were more likely to suffered from sarcopenia. HMB supplementation had shown its increase effect on appendicular skeletal muscle and could attenuated muscle wasting in elderly people.