Abstract: Micromelalopha troglodyta is the main pest of eating leaves for damaging Populus spp. , It has five generations a year in Xuzhou district,Jiangsu province and overwinters as pupa. The first generation is the accumulating stage of the popularity base. The second generation is the reproducing stage of the popularity number. The third and fourth generations are the disastering stage. This paper reports this kind of pests life history, development period, living custom and natural enemy in detail.