Abstract: Outer space mutation breeding has become an important characteristic of mutation breeding in china. The first variety of alfalfa bred by space mutation in China is ‘Hangmu No.1’.The characteristic of Hangmu No.1 alfalfa are high multifoliate rate, hay yield and nutrient content. To test the productive performance of Hangmu No.1, comparative testing was conducted in Lanzhou. The results indicates that Hangmu No.1 had significantly increased leaf mass, 5.72% higher than controls; Hay yield was 14237.5 kg/ha, 13.26% higher than the control varieties; crude protein content from the first and second harvest (anthesis stage) were 20.08% and 18.42% respectively, 2.97% and 5.79% higher than control varieties. Essential amino acids and trace element contents were also significantly higher than control varieties. Correlation analysis between multifoliate rate and others agronomic traits revealed that multifoliate rate was significantly positively correlated with hay yield, crude protein content, and amino acid content. This study indicates that the multifoliate trait can improve yield and nutritional value of alfalfa hay.