The invention discloses a compound pesticide for preventing and controlling liberobacter asiaticum and a preparation method thereof. According to objective requirements of prevention and control of liberobacter asiaticum, ZhongShengmycin and oxytetracycline hydrochloride are used as sterilization pesticides, salicylic acid is used as an anti-disease regulation agent and alpha-naphthalene acetic acid is used as a rooting accelerant; the materials are reasonably blended, and pesticide application is carried out by adopting a trunk infusion method, so that the advantages of the agents are complementary to each other; and the compound pesticide has the properties of high efficiency, low toxin, safety, economy and multiple functions, and can be used for preventing and controlling liberobacter asiaticum very well.