Abstract: Toxicity of abamectin and rubble seed oil against Tetranychus cinnabarinus and joint action of their mixture were evaluated in the lab. It was showed that, for the toxicity of abamectin and rubble seed oil to adult famales of Tetranychus cinnabarinus, the LC50 value were 0.01μg/ml and 1311.81μg/ml respectively. Abametin-rubble seed oil combination had prominent addictive effects on Tetranychus cinnabarinus, and the proportion (1:99) of abamectin and rubble seed oil was the most significant with the co-toxicity coefficient of 293.90. Abamectin and the best combination had low activities to eggs, but they had outstanding toxicity to nymphs hatched from the treated eggs, and the combination was much better than abamectin with the same dosage. It could be drawn that the bio-pesticide combination of abamectin and rubble seed oil with the characters of high effects and safety could be widely applied in the controlling of Tetranychus cinnabarinus.