The biochemical composition(C, N elements, fat, carbohydrate, ash and amino acids) of Prorocentrum donghaiense was analyzed and the effects of P. donghaiense and Alexandrium catenella on the transport of materials through a simulated marine food chain (algae→Artemia salina) were investigated. The results showed that the content of phenylalanine, histidine and lysine in P. donghaiense was obviously lower than in other dietary microalgae. Fed with P. donghaiense solely, the gross conversion efficiencies (GCEs) of A. salina increased gradually when the algal densities were lower than 4×104cells/mL, and decreased gradually at higher densities. When fed with the mixture of P. donghaiense and the diatom Nitzschia closterium, A. salina preferred grazing on P. donghaiense to N. closterium, and the GCEs of A. salina decreased with the increasing density of P. donghaiense. When exposed to A. catenella at the densities of 10-103cells/mL, A. salina lost weight with no Chlorophyll a detected in their guts, which indicated that A. salina didn’t ingest the algal cells. When the re-suspended cells and cell-free medium of A. catenella were mixed with N. closterium or P. donghaiense respectively, the grazing and GCEs of A. salina were all diminished. Consequently, based on the results from this simple food chain model, we propose that the large-scale blooms of P. donghaiense and A. catenella in the East China Sea could adversely affect zooplankton due to insufficient food or nutrition, and therefore impact the materials transfer efficiency through the food chain.