The aim of this study was to investigate the effects of urea supplementation in a low protein diet on growth and development and blood indices of meat rabbits. A single factor randomized block design was used in the experiment. One hundred and twenty New Zealand rabbits at 50 days of age with the similar body weight were randomly allotted into 4 groups with 15 replicates per group and 2 rabbits per replicate. One group was the control group and the rest groups were the experimental groups. The rabbits in the control group were fed a basal diet with 11.11% crude protein, and the rabbits in the 3 experimental groups were fed the basal diets supplemented with 1%, 2% and 3% urea by the way of the starea, respectively. The duration of the preliminary experiment was 10 d and the duration of the formal experiment was 30 d. The results showed as follows: on the second day of the experiment, 80% of rabbits in 3% urea group were dead because of ammonia poisoning.The final weight, weight gain and average daily gain of rabbits in 1% urea group were significantly higher than those in the control group and 2% urea group (P<0.01). Compared with the control group, the whole blood ammonia nitrogen content and serum glutamic pyruvict ransaminase activity of rabbits in 1% and 2% urea groups were significantly increased (P<0.05 or P<0.01), while the liver weight and coefficient were significantly decreased (P<0.05 or P<0.01). Compared with the control group and 1% urea group, the dry matter daily intake, carcass weight and dressing percentage of rabbits in 2% urea group were significantly decreased (P<0.01), while the ratio of feed to gain was significantly increased (P<0.01). The urea nitrogen content and activities of glutamic-oxalacetic transaminase and alkaline phosphatase in serum of rabbits in 2% urea group were significantly higher than those in the control group and 1% urea group (P<0.01). Compared with the control group and 1% urea group, the weight of heart, spleen and kidney of rabbits in 2% urea group were significantly decreased (P<0.05), while the kidney coefficient was significantly increased (P<0.01). The stomach weight, duodenum weight and length, jejunum weight and length, caecum weight and coefficient, appendix weight, coefficient and length, large intestine weight and length of rabbits in 2% urea group were significantly lower than those in control group and 1% urea group (P<0.05 or P<0.01), and the ileum coefficient and caecum length were significantly lower than those in the control group (P<0.05 or P<0.01). In conclusion, low protein diet supplemented with 3% urea can cause the death of the meat rabbits because of ammonia poisoning, 2% urea can cause the stagnancy of growth and development, and 1% urea can improve the growth and finishing performance, but has a negative effect on the development of liver.