Abstract: To investigate the effects of dietary combinations of zeolite, plant extract and vermiculite (ZEM®) on growth performance and histological intestinal changes, male Sanuki Cochin chickens were allotted to 3 groups of 12 birds each. They were fed ad libitum on a basal commercial mash diet with 0 (control), 1 and 2 g kg-1 dietary ZEM®. A starter diet (CP, 21%; ME, 3,000 kcal kg-1) was fed to chickens until 28 day of age, at which point a grower diet (CP, 18%; ME, 2,850 kcal kg-1) was fed until 70 day of age. Feed intake and body weight gain tended to increase with increasing levels of dietary ZEM® and feed efficiency tended to be highest in the 1 g kg-1 ZEM® group. Most intestinal villus height, villus area, cell area and cell mitosis numbers were better than those of the control group and the duodenal cell areas and cell mitosis numbers of all intestinal parts were greater (p<0.05) in the ZEM® groups than in the control group. Protuberated cells were observed on the villus tip of the ZEM® groups. These histological changes indicate that the intestinal villi and epithelial cells were hypertrophied by ZEM®. The present results suggest that chicken growth performance would be improved due to hypertrophied intestinal villi and epithelial cells after feeding ZEM® and that ZEM® is effective alimentation for chicken diets.