The invention relates to a method for degrading landscaping garbage to produce an organic fertilizer by utilizing high-efficiency mixed bacteria, which comprises the steps: (1) organic matters of the landscaping garbage are sterilized after being crushed; (2) nutrition substrates, lignin and cellulose degradation bacteria are added to the solid phase; (3) the mixture is irradiated for 20 minutes every other 8 hours by adopting low-frequency ultrasonic wave until the fourth to seventh day of the fermentation cultivation after the fermentation cultivation for 24 to 26h; and (4) the sterilization processing is carried out to obtain the finished product organic fertilizer after the thoroughly decomposition for 1 to 3 days. The method has the advantages of simple required equipment, simple andconvenient process, and safety disposal realization of the landscaping garbage. Meanwhile, the method produces the organic fertilizer capable of promoting the growth of crops, solves the difficultiesof difficult degradation and difficult recycle of the current landscaping garbage, and has extremely profound social significance and economic value.