Abstract: Indoor toxicity of novel compound tenvermectin against Plutella xylostella (residual film method), Mythimna separate Walker (Leaflets disk method), Helicoverpa armigera Hübner (dietcorporated method), Bursaphelenchus xylophilus (impregnation method) and Tetranychus cinnabarinus (slide dipmethod and leaf-spraying method) were determined. And the pot efficacy of T. cinnabarinus was determined by the leaf-spraying method. The control efficacy against T. cinnatarinus on broad bean seedling was also evaluated. The results showed that the LC50 value of tenvermectin against P. xylostella, M. separate, H. armigera and B. xylophilus were 22.21, 19.66, 22.09 and 1.94 mg/L, respectively. The result showed that toxicity of tenvermectin and milbemycin differed significantly with LC50 value difference (P50 value of tenvermectin against alduts of T. cinnatarinus were 0.005 1 and 0.008 9 mg/L determined by leaf-dipping method and slide-dip method, respectively. Results of pot experiments showed the efficacy against T. cinnatarinus was 80.23%-91.96% at the dosage of 0.0125-0.2 mg/L after the application of tenvermectin. The control efficacy reached the highest (97.42%) 5 days after the treatment at 0.2 mg/kg. However, it started to decrease 7 days after the treatment. The results indicated that tenvermectin is a compound with great potential.