According to the research finding for the limnology, in the whole lake ecosystem it should be including benthic pathway and pelagic pathway, while the variation of nutrition conditions can significantly change the structure and function of the bethic-pelagic coupling foodweb. In order to certain the effects of eutrophication on the benthic-pelagic coupling foodweb in shallow lake ecosystem, Baiyangdian Lake as the study area. Field samping and ECOSIM with ECOPATH(EwE) model method were applied in this study, the conceptual model for benthic-pelagic coupling foodweb in Baiyangdian Lake was established, the effects of eutrophication on the benthic-pelagic coupling foodweb was monitored during the period of 1982-2011. The research finding was:(1) the result for the filed sampling was showed that the nutrition condition for Baiyangdian Lake was belonged to eutrophication from 1999 to 2011; (2) the result for the EwE model was showed that the total biomass of Baiyangdian Lake was decreased for 66.38%, and the main energy pathway was changed from benthic pathway to pelagic pathway; (3) through Pearson correlation analysis, the phytoplankton was showed significantly positive correlation with TN (r=0.67, P < 0.01) and TP(r=0.37, P < 0.05) while the periphyton and macrophyte were showed significantly negative correlation with TN (r=0.77, P < 0.01; r=0.67, P < 0.01) and TP (r=0.54, P < 0.01; r=0.36, P < 0.05). Therefore, eutrophication is the main driving force for the change from benthic primary and secondary productivity to pelagic primary and secondary productivity. Applying scientific method to evaluate the effects of eutrophication on the pelagic-benthic coupling foodweb is very important, it also can help to provide technology and method to the lake ecosystem management.