Maternal separation in early life can increase vulnerability to neuropsychiatric disorders over the lifespan. To investigate the effect of acupuncture on cell proliferation in the dentate gyrus (DG), 5-bromo-2'-deoxyuridine (BrdU)-immunohistochemistry was performed in maternally-separated rat pups. Maternal separation, for 7 days from postnatal day 14, induced a significant decrease of BrdU-immunoreactive cells in DG, while acupuncture treatment at acupoint Shenmen (HT7), at the end of the transverse crease of the ulnar wrist, resulted in the significant increase in the number of BrdU-positive cells in DG. However, acupuncture at acupoint ST36, near the knee joint, produced no increase in the number of BrdU-positive cells. These findings indicate that acupuncture at acupoint HT7 appears to stimulate cell proliferation, and we suggested that acupuncture may be useful in the treatment of diseases related to maternal separation.