Abstract: In order to find out the life cycle and biological habit of Dendroctonus armandi,the methods of laboratory experiment and field trial were adopted to study D. armandi. The results showed that D. armamdi would produce one generation per year or three generations in two years with obvious overlapped generations in Nanjiang. Overwintering larvae in the phloem were main,and a few number of adults and eggs were also found in winter. Overwintering larvae pupated in late March, reached maximum from April to May, adults flied in late April, reached maximum from May to June. Spawning period began in late April, and new generation of adults began to fly in July, while some larvae directly went into the overwintering phase.