The invention provides application of a migratory locust intestinal tract RNase gene 2 to agricultural pest prevention and control. Particularly, by a bioinformatic method, RNase 2 fragments are obtained from a migratory locust transcriptome; the cDNA full length sequence is obtained through PCR (polymerase chain reaction) amplification verification. The double-chain RNA (dsRNA) of RNase 2 is synthesized according to the design primer; after the injection into the migratory locust body cavity, the specific silencing RNase 2 can be performed; then, after the migratory locust is fed with insect-resistant gene DsRNA, the migratory locust death rate can reach 50 percent or higher; through the application of the RNase 2, the pest prevention and control through dsRNA feeding becomes possible; important practical significance can be realized on the pest prevention and control.