Effects of taurine enrichment on the population growth and reproduction of rotifer,Brachionus rotundiformis were studied.Rotifers were enriched with 4 levels (each with 4 repetitions) of taurine,0,0.4,0.8,1.2 g/L,respectively and the culture lasted for 264 h.The results showed that the population growth of rotifer in the treated groups were significantly different from the control (P<0.01) and the population density was significantly higher in the 0.8 g/L group than in the other groups (P<0.01) during the culture period.The population density and growth rate reached the maximum at 144 h in the control and at 168 h in the treated groups,with the highest density appeared in the 0.8 g/L group.The population growth decreased significantly in the control (P<0.01) after 168 h.The egg ratio of the control increased rapidly during 0-24 h and decreased rapidly during 168-264 h.While in the treated groups,the egg ratio increased and decreased slowly.In conclusion,taurine could be a positive factor to enhance reproduction and population growth of rotifers and the optimal concentration was 0.8 g/L.