Abstract: In order to determine the control effect of ally isothiocyante(AITC) against longicorn beetles, the dosages and fumigation time of AITC to longicorn beetles larva, the treatment method of the tunnels and seals were studied in this paper. The results showed that by using 0.5-1.0 mL AITC per tunnel, the control effect was more than 96.7% one day after treatment, and the inside of the tunnels need not to be cleaned and using kaolin and plastic film to seal the tunnels. We can draw the conclusion that AITC was a very effective botanical insecticide to control longicorn beetles.