Abstract: Under the same conditions,a solid-state fermentation using Aspergillus niger,Candida utilisand Bacillus subtilis was carried out to compare the effects of single strains or mixed strains on the nutritional components,antinutritional factors and antioxidant activities of Moringa oleifera stem and leaf powder.The results showed that the effect of mixed strains fermentation were superior to single strain.Compared to the control group with equal amount of sterilized water,Moringa oleifera stem and leaf powder fermented by combination of Aspergillus niger and Bacillus subtilis or mixed fermentation of Aspergillus niger,Bacillus subtilis and Candida utilis showed that the contents of crude protein,acid soluble protein,reducing sugar,in vitro protein digestibility,neutral detergent fiber and acid detergent fiber were changed significantly(p<0.05).Antinutritional factors such as hydrolyzed tannin,saponin and phytic acid all decreased,and antioxidant activity significantly increased(p<0.05). In general,mixed strains fermentation have a wider application prospect than single strain fermentation.The best choice for improving the nutritional quality and antioxidant activity of Moringa oleifera stem and leaf powder is the mixed fermentation of Aspergillus niger,Bacillus subtilis and Candida utilis.