The toxicity experiment in the lab shows that, the aconitic steep has high toxicity against Myzus persicae (Sulzer)and Macrosiphum rosivorume Zhang, which are commonly found in ornamental horticultural plants, LC50 being 14.99 and 15.07 times’ diluted original steep. The laboratory experiment shows, after 48h the corrected mortality rates of 10 times’ diluted aconitic steep against the Myzus persicae (Sulzer)and Macrosiphum rosivorume Zhang reach 85.56% and 89.94% respectively; And after 48h the corrected mortality rates of 15 times’ diluted aconitic steep against the peach aphid and China rose aphid reach 79.97% and 81.08% respectively. Using DMRT at a level of 5%, there are no significant differences between the aconitic steep and the 40% omethoate E.C. 1500× or the 45% malathion E.C. 1000×, which are commonly used field chemical pesticide.