The effect of hen dietary 25-OH-D₃ (added 3000 IU to control diet with 1000 IU) on the morphological changes of the small intestine of Ovambo chicks during prehatch and posthatch period was investigated. After 2 week feeding hens with the experimental diets, eggs were collected and incubated. Results show that the weight, length, thickness of small intestine and the height, perimeter and surface area of villi in small intestine increased with age, and they increased faster in jejunum and duodenum (P<0.05) than in ileum. Comparison with the control diet, 25-OH-D₃ supplement in maternal diet caused the lower weight and shorter length of the small intestine of offspring after hatch (P<0.05). Meanwhile, 25-OH-D₃ of maternal diet induced the increase of the villi height and the crypt depth in the three segments after hatch, in particular in the jejunum and duodenum (P<0.05). We suggest that dietary 25-OH-D₃ can be used as a feed additive in maternal diet to stimulate morphological maturation and in consequence intestinal function in chicks during later incubation and the first week of life.