Abstract: The aim of this study was to investigate the effect of dietary protein levels on growth performance and carcass composition so as to investigate the suitable dietary protein level according to the best lean meat growth and carcass composition by Fuzzy Comprehensive Judgment Model. Ninety pigs were randomly allotted into five groups fed diet containing different protein levels. There are eighteen pigs in each group with three replicates. Six pigs were used in per replicates. The experiment was designed by single factor random arrangement. The dietary protein levels were high high protein（HHP, 18%, 16% and 14%）, high medium protein（HMP, 17%, 15% and 13%），medium medium protein（MMP, 16%, 14% and 12%）, medium low protein（MLP, 15%, 13% and 11%）and low low protein（LLP, 14%, 12% and 10%）respectively during 15.30, 30-60 and 60-100 kg body weight. The daily gain and feed efficiency were calculated. The carcass composition was measured when the pigs were slaughtered at 30, 60 and 100 kg body weight. Fuzzy Comprehensive Judgment Model was analyzed to make sure the suitable dietary protein level to attain the best growth performance and carcass composition in Wujin pigs during different growth stages. The results showed that dietary protein levels affected significantly the growth performance and carcass composition during different growth stages. With dietary protein level decreased, the daily gain reduced but the ratio of feed to weight increased gradually. The difference was significant among high group, medium group and low groups during 30-60 and 60-100 kg body weight. The time reaching 100 kg body weight of five groups were the days of 163, 168, 173, 179 and 185, respectively. The carcass composition except for suet weight and loin eye area were no significant difference among each groups at 30 kg body weight. Lean meat weight, lean meat percentage and loin eye area decreased, but fat meat weight, fat meat percentage and backfat thickness increased with dietary protein levels reducing at 60 and 100 kg body weight. Moreover, the differences were significant among high, medium and low groups. Fuzzy Comprehensive Judgment Model was analyzed basing on the lean meat weight. The suitable dietary protein levels were 15.95%, 14.30% and 11.81% during 15-30, 30-60 and 60-100 kg body weight respectively from the fitting curve. Fuzzy Comprehensive Judgment Model was draw depending on the lean meat percentage, backfat thickness and loin eye area which represented the carcass composition. The suitable dietary protein levels were 16.47%, 13.71% and 10.72% during 15-30, 30-60 and 60-100 kg body weight, respectively. It was revealed that the suitable dietary protein levels were 14.98%, 11.34% and 11.71% combined lean meat growth with carcass characteristics by Fuzzy Comprehensive Judgment Model. This result could provide scientific basis for the reasonable feeding of Wujin pigs.