The experiment was conducted to determine the effects of aflatoxin-detoxifizyme on growth performance, serum and liver histological changes of Lingnan yellow broilers fed a basal diet with aflatoxin B1. Four hundred and twenty 1-day-old Lingnan yellow broiler chicks were randomly divided into 7 treatments, and 4 replicates in each treatment and 15 yellow broiler chicks including 10 roosters and 5 hens in each replicate. The 7 groups were as following: basal diet, basal diet+100 μg/kg aflatoxin B1, basal diet+100 μg/kg aflatoxin B1+0.1% aflatoxin-detoxifizyme, basal diet+100 μg/kg aflatoxin B1+0.2% aflatoxin-detoxifizyme, basal diet+100 μg/kg aflatoxin B1+0.3% aflatoxin-detoxifizyme, basal diet+100 μg/kg aflatoxin B1+0.4% aflatoxin-detoxifizyme, basal diet+100 μg/kg aflatoxin B1+0.5% aflatoxin-detoxifizyme. The experiment lasted for 42 days. The results showed that 1) growth performance of broilers fed 100 μg/kg aflatoxin B1 was affected: average daily feed intake (ADFI), average daily gain (ADG) and average final weight (AFW) were decreased (P>0.05); the contents of total protein, albumin and globulin in serum of broilers fed 100 μg/kg aflatoxin B1 were decreased (P<0.05, P>0.05, P<0.05), but activities of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) were significantly increased (P>0.05); generalized necrosis of liver and abnormal proliferation of bile duct of broilers fed 100 μg/kg aflatoxin B1 were found through liver tissue sections; 2) supplementation of aflatoxin-detoxifizyme in 100 μg/kg aflatoxin B1 diet improved ADFI, ADG and AFW of chickens to a certain degree (P>0.05), and 0.2%, 0.4% and 0.5% aflatoxin-detoxifizyme significantly decreased residues of aflatoxin B1 in liver and blood (P<0.05) and reduced the hazard of aflatoxin B1 to liver, and improved serology indexes to a certain degree. In conclusion, aflatoxin-detoxifizyme could efficiently protect the liver, reduce or almost eliminate the negative effects of aflatoxin B1 on organs of Lingnan yellow broiler chickens, and improved ADG and ADFI to a certain degree.［Chinese Journal of Animal Nutrition, 2010，22（2）:424-430］