Abstract: For improving forecasting and sustained control damage level， light trap numbers and field dynamic of underground pests (black cutworm， mole cricket and scarab beetle) in Hangzhou district during the years of 2005 to 2011 were investigated The results showed that different pests had obvious differences in population dynamic The black cutworm， Agrotis ypsilon， had several damage peaks (late May， late June and late July etc)， and the moth amount of the prophase was relatively high The mole cricket， Gryllotalpa africana， had two damage peaks (late May to early July， early September to middlelate October) The scarab beetle， Anomala corpulenta， had one damage peak (late May to late June) There were periodic changes in total numbers of underground insect pests among years， and the peak period was the year of 2005， 2007 to 2009 and 2011， respectively On this basis， temperature， humidity， precipitation， illumination etc were used as forecasting factors， using the method of stepwise regression， nineteen factors with significant correlation were screened， and occurrence amount forecasting models and occurrence period forecasting models of the three insects were established By using accuracy degree judge model for verification， the score values of occurrence amount and occurrence period forecasting models of the three underground pests were more than 58 and 70， which indicated that the historical coincident rate and prediction accuracy of established forecasting models were good.

Key words: Hangzhou district, underground pests, population dynamic, occurrence regularity, prediction model