Tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is one of the most important tomato pests around the world, which its larvae feed on leaf and stem and fruit and causing significant damage to the crop. This pest has 10-12 generations per year. Its damage to the tomato crop can reach up to 100 % in the absence of natural enemies and suitable chemical control. Nesidiocoris tenuis (Hem.: Miridae) prey actively on eggs and all larval stages of this pest. In the current study, bioassay experiments were conducted at 25 ± 2°C, 60 ± 5% RH, and photoperiod 16:8 L: D. The toxicity of lufenorun and flubendiamide pesticides was carried out on the last larval stage (stage 4) by immersion of leaves in a toxic solution and fifth instar nymphs predator by a residual toxicity method in a glass petridish. Data probit analysis was performed by Polo-Pc software. Lethal concentrations of lufenorun and flubendiamide were obtained after 24 and 48h on larvae of T. absoluta and nymph of N. tenuis, respectively. The LC50 values of lufenorun and flubendiamide on T. absoluta larvae were calculated as 4.35 and 125.41 mg/ml, respectively. The results showed that lufenorun had higher toxicity to the larvae of T. absoluta than flubendiamide. Also, the LC50 of lufenorun and flubendiamide was 407.86 and 7.09 mg/ml, on fifth instar nymph of N. tenuis, respectively. This study can be useful in the development and evolution of integrated pest management methods. However, further studies are necessary to do by field surveys.