Abstract: Platylomia pieli Kato,an underground bamboo pest,completes the development of one generation in 6 years in Zhejiang,with eggs and nymph overwintering on dead branches and in soil respectively.Adults occur through late June or early July to mid September,feeding on branches of bamboo and other tree species by sap sucking.Eggs,12～21 eggs per hole,are laid in dead,2～3 year old branches,and hatch in early July of the following year.The nymphal stage has 5 instars.They live in soil with 5 to 40 cm in depth,and feed on bamboo roots.Nymphs live individually,and are aggressive and attack each other when two or more of them meet,leading to heavy wounds or death.Platylomia pieli is rich of natural enemies,of which the wasp,Eupelmus sp.,is the most important,and its larvae destroys 38.3%～41.4% Platylomia pieli eggs. Sandalus sp.,another key enemy,kills 28.7%～32.58% P.pieli larvae.Isaria cicadae Maquel is the main nymph parasitic fungi.