Abstract: Eriococcus rugosus Wang, an important new insect species damaged bamboos in the recent years, are distributed in Anhui, Jiangsu, Shandong, Shanghai and Zhejiang. E. rugosus has one generation per year in Fuyang County of Zhejiang Province, overwintering as the second instar nymph and male prepupa. Adult males appear in late March. Most of the third instar nymphs turn into adult female in early April and deposite eggs in early May. The first instar nymphs infected the bamboo shoot bud, appear in early May. The second instar ones oversummer in late October. The cocoon males appear in early November, then overwinter. There is a maximum population density in 2-year-old bamboo groves, medium in 4-year-old ones, minimum in 6-year-old or over 6-year-old ones. The percentage of groves damaged by the pest is up to 100%, 92% and 50%, respectively. The effective control of the pest can be achieved by injecting 50% methamidophos emulsion 2ml to each bamboo from middle March to middle April.