NOVELTY - Iron-rich bio-organic fertilizer comprises 60-80 pts. wt. edible mushroom waste residue, 15-35 pts. wt. humic acid, 5-15 pts. wt. phellodendron, 5-10 pts. wt. chelated iron and ferric citrate in a mass ratio of 1:1-2, and 0.2-2 pts. wt. composite microbial inoculum. The composite microbial inoculum comprises traditional organic material leavening agent and functional bacterial composition comprising Bacillus amyloliquefaciens and Trichoderma atroviride in a mass ratio of 1-2:1. The total number of viable cells in organic fertilizer is greater than or equal to 0.500000000 cells/g.    USE - The bio-organic fertilizer is useful for producing green vegetables (claimed), and improving soil physical and chemical properties, and preventing soil-borne disease.    ADVANTAGE - The bio-fertilizer increases crop yield, and nutritional quality in the product.    DETAILED DESCRIPTION - Iron-rich bio-organic fertilizer comprises 60-80 pts. wt. edible mushroom waste residue, 15-35 pts. wt. humic acid, 5-15 pts. wt. phellodendron, 5-10 pts. wt. chelated iron and ferric citrate in a mass ratio of 1:1-2, and 0.2-2 composite microbial inoculum. The composite microbial inoculum comprises traditional organic material leavening agent and functional bacterial composition, where the active components of bacterial composition include Bacillus amyloliquefaciens and Trichoderma atroviride in a mass ratio of 1-2:1. The total number of viable cells in organic fertilizer is greater than or equal to 0.500000000 cells/g, the organic matter content is greater than or equal to 40%, moisture content of less than or equal to 30%, and pH of 6-7.5. An INDEPENDENT CLAIM is also included for preparing the fertilizer, comprising (i) drying edible mushroom waste residue, and mixing with rapeseed meal, and crushing to 200-300 meshes; (ii) adding humic acid into crushed materials, and adjusting the water content to 50%; (iii) adding 0.2-1 wt.% traditional organic material leavening agent into the mixture, stacking the fermentation mixture up to a height of 1-1.2 m, at room temperature, and carrying out aerobic solid fermentation for 7-10 days, where the fermentation temperature is 50-70 degrees C, continuing the fermentation process for 15-30 days; (iv) drying the fermented organic materials, controlling the temperature below 80 degrees C, and controlling the moisture content below 30%; (v) adding chelated iron and ferric citrate into the organic material, and uniformly mixing; and (vi) adding Bacillus amyloliquefaciens and Thermophilic sporotrichum into the organic material prepared, and uniformly stirring to obtain the product.