The study was aimed to investigate the effects of human bone marrow mesenchymal stem cells (MSCs) in the radiation-induced intestinal injury. MSCs were expanded, labeled with enhance green fluorescentprotein (eGFP). The NOD/SCID mice were randomly assigned to one of three groups: (A) without radiation; (B) and (C) received abdominal radiation with 5 Gy ⁶⁰Co γ-rays at the rate of 100 cGy/min. (B) i.v. transplanted with physiological saline, (C) i.v. transplanted with MSCs. Mice were weighed daily and observed for 15 days after irradiation. Intestines of mice were obtained in order to assay histological changes by hematoxylin and eosin staining. The immunofluorescence staining showed that the transplanted cells could differentiate into vimentin+/α-SMA+ fibroblastic-like cells in vivo. These data indicated that MSCs could engraft at the injured small intestine, and contribute to the repairment of irradiated intestine. This could provide a valuable strategy for radiation-induced enteritis.