The differences of nutrition components and active ingredient between Avena nuda and Avena sativa were compared. The contents of basic components (moisture and ash), nutritional compositions (starch, protein and fat) and functional active ingredient (flavonoids, polyphenols and oligosaccharide) in 5 kinds of Avena nuda and 3 kinds of Avena sativa were determined. The results showed that there were no significant differences in the contents of moisture and ash between Avena nuda and Avena sativa. The contents of crud fat, crud protein, stearic acid, oleic acid, linoleic acid, linolenic acid, flavonoids and amino acid in Avena nuda were significantly higher than those in Avena sativa, while the contents of slowly digestible starch and stachyose in Avena nuda were significantly lower than those in Avena sativa. Both Avena nuda and Avena sativa had similar composition of nutritional and functional active ingredients but the contents of them higher in Avena nuda than in Avena sativa.