Abstract: There are about 10 kinds of natural enemies of Myzus persicae in tobacco fields,especially of Chrysopa sinica Tieeder and Aphidius gifunesis Ashmead in this area.Under the control of all kinds of natural enemiest there are effective results to Myzus persicae population in the middle of May and June.And then,after tobacco planted in fields for 30-40 days,natural enemies can mutiply quickly after immigrant.It is also the good time to resist the destroying of pests under the common effect of different kinds of species.Yet,it is not a good idea to use chemical insecticides to control Myzus persicae and other insect pests in this stage,but to adapt the agricultural control and biological control. When their demages surpass the economic threshold,it is appropriate to control insect pests by chemical pesticides.