This experiment was conducted to study the effects of dietary saccharicterpenin level on mucosal structure of small intestine in Gushi chickens. A total of 300 Gushi chickens were randomly assigned to five dietary treatments: control (basal diet) group, 300 mg/kg saccharicterpenin group, 500 mg/kg saccharicterpenin group, 700 mg/kg saccharicterpenin group and chlortetracycline (200 mg/kg) group. Each group had three replicates and each replicate had twenty chickens. Six chickens at 21, 35 and 49 days of age were picked in each group and bled to death. Using the conventional paraffin sections and HE staining, the mucosal structure of the duodenum, jejunum and ileum were observed, and then the villus height, crypt depth and intestinal wall thickness were measured. The results showed as follows: 1) there were no significant differences among all groups in the length of duodenum, jejunum and ileum and the thickness of intestinal wall in Gushi chickens aged different days (P>0.05). 2) At different ages, the duodenum villi height of Gushi chickens in the 500 mg/kg saccharicterpenin group and 700 mg/kg saccharicterpenin group was higher, and there was no significant difference between the two groups (P>0.05), but at 21 days of age, it was significantly higher than that in the other groups (P<0.05); at 35 to 49 days of age, it had no significant difference compared with that in the other groups (P>0.05). At different ages, the duodenum V/C value of Gushi chickens in the 500 mg/kg saccharicterpenin group and chlortetracycline (200 mg/kg) group was higher, and there was no significant difference between the two groups(P>0.05), but at 21 to 35 days of age, it was significantly higher than that in the control group (P<0.05); at 49 days of age, it had no significant difference compared with that in the other groups (P>0.05). 3) At different ages, the jejunum villi height of Gushi chickens in the 500 mg/kg saccharicterpenin group was the highest, and at 21 to 35 days of age, it was significantly higher than that in the control group (P<0.05), but it had no significant difference compared with that in the 700 mg/kg saccharicterpenin group and chlortetracycline (200 mg/kg) group; at 49 days of age, it had no significant difference compared with that in the other groups (P>0.05). At different ages, the jejunum V/C value of Gushi chickens in the 500 mg/kg saccharicterpenin group, 700 mg/kg saccharicterpenin group and chlortetracycline (200 mg/kg) group was higher, and there were no significant differences among the three groups (P>0.05), but it was significantly higher than that in the control group (P<0.05). 4) At different ages, the ileum villi height of Gushi chickens in the 700 mg/kg saccharicterpenin group and chlortetracycline (200 mg/kg) group was higher, and at 21 to 35 days of age, it was significantly higher than that in the control group and 300 mg/kg saccharicterpenin group (P<0.05), but it had no significant difference compared with that in the 500 mg/kg saccharicterpenin group (P>0.05); at 49 days of age, it had no significant difference compared with that in the other groups (P>0.05). At different ages, the ileum V/C value of Gushi chickens in the 500 mg/kg saccharicterpenin group, 700 mg/kg saccharicterpenin group and chlortetracycline (200 mg/kg) group was higher, and there were no significant differences among the three groups (P>0.05), but it was significantly higher than that in the control group. These results indicate that saccharicterpenin supplementation can promote intestinal villus growth and reduce crypt depth, which increase the nutrient absorption cross section of intestinal wall. Accordingly, the suitable saccharicterpenin supplemental level is 500 mg/kg.