Objective To explore the role of cell proliferation and apoptosis, and the expression significance of involved protein as Bcl-2 (B-cell lymphoma/leukemia-2) and Bax (BcL-associate X protein) in the developing small intestine of human fetus. Methods The expression product of Bcl-2 and Bax was investigated with immunohistochemical methods in the 2nd, 3rd and 4th months of gestation respectively. Results In the second, the third and the fourth month of gestation, the Bcl-2 immunoreactive positive signals were found in the ganglion cells of intermuscular and submucous nerve plexus. Bax positive cells were observed in the cytoplasm of the simple columnar epithelium cells of the small intestinal mucous layer.Conclusion Bcl-2 and Bax proteins regulate the developing small intestine of human fetus.