The research of biological control the 2nd generation Asian corn borer was conducted using unmanned aerial vehicle to spray Beauveria bassiana, Metarhizium anisopliae and Baci1lus thuringiensis synthetically in field.The result shows that pest density, percentage of damaged plants, percentage of borehole, and length of borehole in treatment of B. bassiana with M. anisopliae were significant lower than other treatments and the control, which indicated that the treatment achieved significant control effect. The results shows that the biocontrol technology of biological control can achieve good control effect in the specific control period of specific pests.