This paper reported the effect of Cu2+ on Rotifer Brachionus calyciflorus.The experimental results showed that the 24h LC50,48h LC50,96h LC50 of Cu2+ to Brachionus calyciflorus were 60.06?μg/L,23.72 ?μg/L,15.07?μg/L.In the solution of 60?μg/L Cu2+,the survivorship,reproduction rate,basic reproduction rate and intrinsic rate of increase were quickly decreased,while the number of resting eggs and the percentage of mictic female produced were greatly increased.