Erythroneura mori has 5 generations per year in middle part and south of Hebei pro-vince,and overwinters as egg under trunk and bark of young tree. Egg hatching begins in the first ten days of May of the next year. The adults appear in the last ten days of May. The second nymphal generation and eclosion to adults appear in the first ten days and the middle ten days of June respec-tively. The third nymphal-,the third adult-,and the forth nymphal-generation appear in the last ten days of June,the first ten days of July,and the middle or last ten days of July separately. In high temp-erature and rainy season,the fifth nymphal generation appears occasionally in the middle ten days of August. The duration of nymphal is about 15 ～ 30d. In the middle ten days of September,the adult oviposits overwintering eggs. The best controlling method is the chemical control with methamidophos( 50% ) at the dilution of 3 000 times. After application,the decrease rate of Erythroneura mori reaches 100% in 24h. The controlling time begins on the explosion of the first nymphal generation.