The aim of this study was to determine the effects of dietary NiCl2 on the development of the small intestine in broilers by the methods of light microscopy, histochemistry and enzyme-linked immunosorbent assay. A total of 240 one-day-old avian broilers were divided into four groups and fed on a corn-soybean basal diet or the same basal diet supplemented with 300, 600 and 900 mg/kg of nickel chloride (NiCl2) for 42 days. Results showed that the small intestinal villus height, crypt depth and villus/crypt ratio were significantly decreased, and also the small intestinal goblet cells numbers and insulin-like growth factor-1 (IGF-1) and epidermal growth factor (EGF) contents were significantly decreased in the 300-, 600- and 900-mg/kg groups when compared with those of the control group. In conclusion, dietary NiCl2 in excess of 300 mg/kg reduced the villus height, crypt depth, the goblet cells population and the IGF-1 and EGF contents in the small intestine, indicating that the normal development and function of the small intestine were finally impaired in broilers. This study firstly provided the new experimental information for future studies on the effects of NiCl2 on the intestinal function in humans and other animals.