The results of field experiment showed that imidacloprid 70% WG had good effect for controlling Wheat Ear Aphid at the dose of 4~5g/667m2. The control effects were over 91% after 1~21days. Besides good effect,imidacloprid 70% WG had other virtues such as long persistent control period,safty to the wheat,environment-friendly characteristic and convenience for use etc. It was an effective and recommendable pesticide for controlling Wheat Ear Aphid.