Abstract: Along 8km extent of the river down from the dam of Zhexi Reservoir in Hunan Province,the population of an insect named Amphipsyche proluta MacLachlan has been rising in great quantities every year.Based on previous reports on the life history and living habits of this caddisfly, the ecological characteristics of this insect, including its water environment for living, reaction to flowing speed and depth of water, its natural enimies situation,and influence from haman activities,are described specially in this paper.It provides theoretical basis for following study on the integrated management of this insect.