Abstract: The present paper deals with the spatial distribution patterns of Dichomer sp. in the seeds yard of cunninghamia lanceolta. Frequency check methods、regression analysis and several aggregation indices were used to determine the spatial distribution patterns. All larval and pupa were of aggregated patterns. Also, the ’aggregation average’ method by Blackith was used to analyse the aggregated reasons of larval and pupa. All larval and pupa were related to their environment; but the function of biological characters only occured with the changing of POPulation density.