A 16-wk feeding trial was conducted to assess the effects of different types of dietary carbohydrate on growth and body composition of juvenile abalone (Haliotis discus). A total of 1,680 abalone were randomly distributed among 24 containers (70 per container) and fed one of eight diets, including seven experimental diets containing different types of carbohydrates, including dextrin (DT), glucose (GC), corn starch (CS), α-cellulose (CL), maltose (MT), sucrose (SC), and wheat flour (WF), and Undaria to compare effect of experimental diets. Water stability of the diets was measured 12, 24, and 48 h after seawater immersion. Water stability of the diets was different over all periods of time and their significant interaction was also observed. Survival was not significantly affected by diet. Weight gain and specific growth rate were greatest in abalone fed on the CL diet. Shell length, width, height, and soft body weight were greatest in abalone fed the CL diet, followed by the WF, DT, SC, CS, GC, and MT diets and Undaria. Weight gain, specific growth rate, crude protein, and crude lipid contents of the soft body of abalone fed on the experimental diets were greater than those fed on Undaria. This study shows that CL is the most effective carbohydrate source for improving growth of this species of juvenile abalone and practically applicable in formulating abalone feed.