Abstract:We examined the excretion of phosphorus and nitrogen of seven common zooplankton species in South China, Brachionus calyciflorus, Asplanchna priodonta, Bosminopsis deitersi, Moina micrura, Daphnia similoides sinensis, Mesocyclops thermocyclopoides and Phyllodiaptomus tunguidus under different temperature (15-30℃). The nitrogen and phosphorus content of the seven species were also analyzed to test the hypothesis that variation in nutrient excretion rate is related to body P and N content. Body P and N content were 4.9-24.2 μg/mg dry weight (DW) and 51.2-153.5 μg/mg(DW) respectively, and their atom ratio was 11.5-43.0. Body P content was significantly related to body dry weight. However, both body N content and N:P ratio were not significantly related to body dry weight. The mass-specific excretion rate of dissolved inorganic phosphorus (DIP) was 0.31-2.10 μg/(mg(DW)·h), negatively related to body dry weight, and positively to temperature and body N:P ratio. The mass-specific excretion rate of total dissolved nitrogen (TDN) was 24-256 μg/(mg(DW)·h), negatively related to body dry weight and positively to temperature. Atom ratio of TDN to DIP excretion was 112-352, positively related to temperature, and negatively to body dry weight and N:P ratio. Our results indicated that zooplankton fed on food with high N:P ratio tend to excrete nutrients with a high nitrogen excretion rate and high ratio of TDN:DIP in South China, and interspecific difference of P excretion and TDN:DIP ratio of the excretion would be ascribed partly to body dry weight and N:P ratio.