The invention belongs to the field of plant protection, and relates to a kasugamycin-containing sterilization composition and an application thereof. The kasugamycin-containing sterilization composition contains effective amounts of A and B, wherein A is kasugamycin, B is one of oxine-copper, copper(succinate+glutarate+adipate), thiediazole copper, humic acid copper, nitroacid copper, copper naphthenate, amino acid copper, copper acetate and sulfamic acid copper, and the mass fraction ratio of A to B is (10:1)-(1:100). The composition can be processed into wettable powder, water dispersible granules, an aqueous emulsion, a microemulsion and a suspending agent, and the mass sum of A and B accounts for 1-80% of the total mass of the preparation. The composition can be used for preventing and treating fungi and bacterial diseases of multiple plants such as rice, wheat, vegetables and fruit trees and has an excellent effect on late blight and gray mold of tomatoes, rice stripe diseases and rice blast, angular leaf spot of watermelons and citrus bacterial canker diseases.