Abstract: Foundamental Courses of Aquatic Products Science. Effects of temperature and shell length on the excretion of nitrogen and phosphorus of Chlamys farreri. The excretion features of farrer’scallop (Chlamy farreri) under simulated natural conditions were studied with the aim of learning the modality of nitrogen and phosphorus excretion, and their excretion rates. Moreover, the investigation of the relationship among water temperature, shell length and alga concentration was also carried out, and some mathematics models about several factors were made. The results showed the excretion rates of DTN and PTN were 14.94 μg·(h·ind) –1 to 248.28 μg·(h·ind) -1 and 1.47 μg·(h·ind) -1 to 84.08 μg·(h·ind) -1，and the excretion rates of DTP and PTP were 0.007 μg·(h·ind) -1 to 42.54 μg·(h·ind) -1 and 0.916 μg·(h·ind) -1 to 17.78 μg·(h·ind) -1. The content of DTN and PTN were 77.2% and 22.8%, there into, the content of ammonia was 50.8%, while the contents of DTP and PTP were 75.6% and 24.4%. The individual total nitrogen and phosphorus excretion rates of the scallop are positively correlated with the shell length and temperature in range of 9.2-27.3 ℃. After considering dissolution and particle excretion of nitrogen and phosphorus, the excretion rates of C.farreri ware related to temperature by quadratic equations, and to shell length by the allometric equations. The interaction of temperature and shell length with DTN，PTN，DTP and PTP could be described by the models VDTN = 131.13Lnt+217.95LnL-617.65, VPTN=67.41Lnt+54.07LnL-242.37, VDTP=8.67Lnt+65.82LnL-112.15 and VPTP=11.73Lnt+11.14LnL-43.74, furthermore, the results of analysis covariance of those models were P<0.01. 22 Refs.In Chinese. Key words:Chlamys farreri; nitrogen; phosphorus; excretion SONG Xian-li(Yellow Sea Fisheries Research Institute of Chinese Academy of Fishery Science, Qingdao266071, China), SUN Yao, WU Jin-xuan, YIN Hui, XU Lin-mei//J Fish China,2007,31(1).38-44