Abstract: The action of tebufenozide(RH 5992) on Chilo suppressalis was investigated by bioassay and field evalution. Tebufenozide disrupted the growth and developing of striped stem borer. The 4 th instar larvae fed with tebufenozide in a dosage higher than 2 mg/L ceased feeding within 2 days, and larvae fed with 0.2 mg/L tebufenozide developed more slowly than the control. Under the concentration of 40 mg/L and 120 mg/L tebufenozide has high efficacy on neonate and 1 to 7 day old larvae ,respectively. The lethal duration varied with the concentration of tebufenozide and larvae instar.The duration of 1～4 th instar larvae was shortened slightly with the increase of the tebufenozide concentration, and it was obvious for 6 th instar larvae. The lethal duration of Chilo suppressalis under lower concentration of tebufenozide was shortened with the increase of larva instar, but was not shortened under higher concentration. Tebufenozide was not effective to eggs and was safe for parasitic wasps. Plotexperiment in paddy showed that a dosage of 1.5 L/hm2 could control Chilo suppressalis, Scirphopaga incertulas, Sesamia inferens and Cnaphalocrocis medinalis effectively.