Abstract: A field experiment was conducted to investigate the nutrient component and amino acids formation contents of alfalfa (Medicago sativa) by selenium (Se) and zinc (Zn) and fulvic acid (FA) combined basal application in alfalfa grassland at Zhongmu Town in Zhengzhou City. The experiment was have five treatments: (1) only applied N, P and K fertilizer, and the fertilized amount was N 90 kg/hm², P₂O₅ 120 kg/hm², K₂O 105 kg/hm²; (2) combined application N, P, K fertilizer and FA (FA applied amount was 90 kg/hm²); (3) combined application N, P, K fertilizer and micro-element fertilizer Se, Zn (ZnSO₄·7H₂O applied amount was 15 kg/hm², Na₂SeO₃ applied amount was 0.60 kg/hm²); (4) combined application N, P, K fertilizer, micro-element fertilizer Se, Zn and FA; (5) CK (there was no fertilizer applied). All the fertilizer was applied as basal fertilizer. And collected the first cut of second year alfalfa was measurement samples. The results indicated that appropriate Se-Zn and FA applied amount could significantly increase herbage yield of alfalfa, and the highest herbage yield was raised to 16.28 t/hm² occurred in the NPK+FA+Zn+Se treatment, higher by 42.43% than that of CK. Applying Se-Zn or FA all could significantly increase the alfalfa Se and Zn content and accumulation. Se-Zn and FA combined application could significantly increase the content of alfalfa crude protein and crude ash, but it there was no significantly effect on crude fat, crude fiber and non-nitrogen extract content. Se-Zn and FA combined application could also increase the contents of total amino-acids (TAA) content and Val, Leu, Lys content and Asp, Arg, His, Tyr content, but had less apparent effects on other amino acid under any condition. The results obtained in this study suggest that appropriate Se-Zn and FA combined application could increase the herbage yield and nutrient and amino acids formation contents of alfalfa and it also favor high quality production.