Abstract: This 137-day experiment was conducted to examine the effect of microencapsulated feed on the immunity and growth of juvenile abalones under the conventional aquaculture practices.The commercially available, formulated abalone feed powder was used as the control.Ten pools of juvenile abalones were allotted to the two groups with 5replicate pens each.The treatment group was fed with a diet consisting of 31% microencapsulated ingredients and 69% Control.The results showed that (a) the AKP and T-SOD activities of the juvenile abalones in the treatment group were significantly higher than those of Control (P<0.05) ; (b) the lysozyme content in the treatment abalones was slightly higher than that of Control, but the difference was not significant (P>0.05) ; (c) the coefficient of variation on the shell length of the treatment abalones was less than that of Control.The treatment abalones appeared relatively uniform on various specifications.The results indicated that the microcapsules had the immune-enhancing, death-rate-lowering and growthpromoting effects on the abalones.And, the growth-promoting effect was found most apparent 71 dafter the abalones were fed with a diet containing the microencapsulated material.