The invention discloses a dendrolimus punctatus cytoplasmic polyhedrosis virus oiling agent, and a preparation method and application thereof. The dendrolimus punctatus cytoplasmic polyhedrosis virus oiling agent is prepared by soaking, chopping, eluting, filtering, centrifugally separating, drying in vacuum, blending and sub-packaging. A dendrolimus punctatus cytoplasmic polyhedrosis virus concentrated liquid is obtained by vacuum drying at 28-35 DEG C in negative 0.9 barometric pressure for 10-15 hours by virtue of a vacuum dryer; and the foul odor of the oiling agent is removed, so that a product is easy to popularize and apply; blending comprises the step of adding saponated glycerinum and analytically pure activated carbon; the content of a dendrolimus punctatus cytoplasmic polyhedrosis virus in the prepared oiling agent is 1500,000,000PIB/ml or above; the pathogenicity of the virus is high; and the expiration date of the oiling agent is prolonged and can reach 3-4 years. By virtue of the oiling agent disclosed by the invention, the infective rate of the dendrolimus punctatus cytoplasmic polyhedrosis virus can reach 95% or above; the oiling agent has a lasting control effect on pine moths in a forest for multiple years after prevention and treatment is performed once; and the lasting control effect can last for five years or above.