The invention relates to a method for preparing an organic fertilizer special for banana fruit trees by using fresh tobacco plant waste of flue-cured tobacco fields. The method comprises the following steps of: (1) collecting and cutting the tobacco plant waste, spraying bacillus licheniformis liquid for fermentation, stacking, filming for heat preservation, turning stacks and air-drying to obtain a fresh tobacco plant waste solid product and a liquid product after preliminary solid fermentation; and (2) uniformly mixing the fresh tobacco plant waste solid product after fermentation and dry chicken manure according to a weight ratio of 35-40:65-60, spraying a zymocyte agent which mainly contains lactobacillus, yeast and photosynthetic bacteria, uniformly stirring and filling in a sealed bag to perform sealed natural fermentation so as to obtain an organic fertilizer product after secondary fermentation. The method has the advantages of low pollution, clean tobacco fields, less tobacco plant diseases, low cost of the organic fertilizer, obvious increase in production of banana, capabilities of improving soil structure, improving land fertility and facilitating heavy metal degradation in plants, improved cold resistance, drought resistance, lodging resistance and resistance to disease and insect of banana plants and high fruit quality.