To investigate the effect of cassava on growth performance and nutrient utilization of meat ducks, a total of 480 meat ducks aged 15 d were randomly allotted to four treatments with six replicates in each treatment and each replicate containing 20 ducks. The four treatments were fed with the diet supplemented with 0, 10%, 20%, 30% cassava respectively for 30 d. The results showed: ① With the increasing of cassava, the average daily feed intake was gradually increased, and the average daily feed intake in the treatment with 30% cassava was significantly higher than that in the treatment with 10% cassava (P<0.05); the gain weight first increased and then decreased. There were significant differences in final weight (45-old weight) and average daily weight gain between the treatment with 20% cassava and the control (P<0.05). The best of gain weight and feed/gain ratio were found in the treatment with 20% cassava. ② The apparent digestibility of dry matter and apparent metabolism energy in diets with 10% or 20% cassava were higher than those in the diets from other two treatments (P<0.05) and the diet with 10% or 20% cassava also showed a increasing tendency in the apparent digestibility of protein. Apart from glycine, arginine, threonine, proline, valine and isoleucine, the apparent digestibility of other amino acids showed no significant difference, but the apparent digestibility of methionine and lysine in the diets with 10% and 20% cassava were higher compared to those in the diets from other two treatments. The results indicated replacing part of the corn with cassava could increase the apparent digestibility of dry matter and protein of meat duck diet to a certain extent, thus increase gain weight and decrease feed/gain ratio, and the optimal supplemental level of cassava in the diet of meat ducks was 10%20%.