To improve forecasting and sustained control level of underground pests, trapping quantity of underground pests (black cutworm,mole cricket and scarab) by lamps and their field dynamics in Hangzhou district from 2005 to 2011 were investigated in the paper. 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) and the moth amount in early period was relatively high. The mole cricket (Gryllotalpa africana) had two damage peaks (late May to early July, early September to mid and late October). The scarab (Anomala corpulenta) had one damage peak (late May to late June). There were periodic changes in total quantity of underground pests among years, and the peak period appeared in the year of 2005, 2007 to 2009 and 2011, respectively. On this basis, temperature, humidity, rainfall and light were used as forecasting factors, using the method of stepwise regression, 19 factors with significant correlation were screened out and prediction models for occurrence quantity and occurrence period of the three pests were established. By using accuracy degree judge model for verification, the score values of prediction model for occurrence quantity and occurrence period of the three underground pests were more than 58 and 70, which indicated that the historical coincident rate and prediction accuracy of established prediction models were good. To improve forecasting and sustained control level of underground pests, trapping quantity of underground pests (black cutworm, mole cricket and scarab) by lamps and their field dynamics in Hangzhou district from 2005 to 2011 were investigated in the paper. 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) and the moth amount in early period was relatively high. The mole cricket (Gryllotalpa africana) had two damage peaks (late May to early July, early September to mid and late October). The scarab (Anomala corpulenta) had one damage peak (late May to late June). There were periodic changes in total quantity of underground pests among years, and the peak on this basis, temperature, humidity, rainfall and light were used as forecasting factors, using the method of stepwise regression , 19 factors with significant correlation were screened out and prediction models for occurrence quantity and occurrence period of the three pests were established. By using accuracy degree judge model for verification, the score values ​​of prediction model for occurrence quantity and occurrence period of the three underground pests were more than 58 and 70, which indicates that the historical coincident rate and prediction accuracy of established prediction models were good.