NOVELTY - Method for preparing biological organic fertilizer using duck excrement fermentation process mixing Bacillus subtilis, lactic acid bacteria, microzyme, photosynthetic bacteria, actinomycetes, Azotobacter, and phosphorus and potassium bacteria, culturing the mixture, performing fermentation at 37 degrees C for 12 hours, adding 2% duck excrement to the fermented mixture, performing kiln furnace type solid fermentation process in a tunnel at 37 degrees C, again performing fermentation process on fermented duck excrement, and performing drying process.    USE - The method is useful for preparing biological organic fertilizer using duck excrement fermentation process (claimed).    ADVANTAGE - The method enables to prepare product which has high soil organic matter, is rich in crop nutrition, promotes plant growth and improves crop yield.    DETAILED DESCRIPTION - Method for preparing biological organic fertilizer using duck excrement fermentation process mixing Bacillus subtilis, lactic acid bacteria, microzyme, photosynthetic bacteria, actinomycetes, Azotobacter, phosphorus and potassium bacteria (equal weight ratio), culturing the mixture, where the cell density of the cultured bacteria is 109 months/ml, performing fermentation at 37?Oc for 12 hours, adding 2% duck excrement to the fermented mixture, and adding water until the water content is 40%, performing kiln furnace type solid fermentation process in a tunnel at 37 degrees C and humidity of 40%, where the upper portion of the horizontal conveyer belt in a fermentation tunnel stack is 200 cm wide and 80-120 cm thick of fermented duck excrement stacking, each day using 45? angle turning, the conveying belt of the duck excrement fermentation stack is transferred to another adjacent of the upper horizontal conveying belt, to realize turning stack fermentation of 15-35 days, again performing fermentation process on fermented duck excrement at normal temperature, and performing storage warehouse, performing drying process on obtained product using direct fired rotary cylinder dryer at 300?, until the water content is not greater than 10%.