The invention discloses a pesticide preparation for preventing and treating the damage of weeds in crops and application, and belongs to the technical field of weed killers. The pesticide preparation is characterized by comprising the following preparation steps: (1) weighing 65-85% of ginkgo fruit epicarp, 14-30% of a solvent and 1-8% of a pesticide adjuvant in percent by weight for spare use; (2) crushing and juicing the fresh ginkgo fruit epicarp in a juicing machine, then adding hydrochloric acid and alcohol according to the ratio, carrying out water-bath heating at the temperature of 45-65 DEG C, stirring for 15-35 minutes, carrying out ultrasonic treatment for 3-5 minutes, centrifuging for solid-liquid separation, and taking supernatant for spare use; and (3) adding sodium lignin sulfonate, lacticcasein and polyoxyvinylalkyl ether into a filtrate, stirring fully and mixing uniformly to obtain a final product. The pesticide preparation disclosed by the invention has the advantages that the production cost is low, the toxic effect is low, no residue is left, the safe effect to the crops is achieved, the weed killing effect is good, and the applicability to multiple worst weeds can be achieved; and the use method is simple, the dosage is low, the effect is good, and the problem of resistance in the application of the existing weed killer is solved.