Preliminary animal experiments have conifrmed that sensory nerve ifbers promote osteoblast differentiation, but motor nerve ifbers have no promotion effect. Whether sensory neurons pro-mote the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells remains unclear. No results at the cellular level have been reported. In this study, dorsal root ganglion neurons (sensory neurons) from Sprague-Dawley fetal rats were co-cultured with bone marrow mesenchymal stem cells transfected with green lfuorescent protein 3 weeks after osteo-genic differentiationin vitro, while osteoblasts derived from bone marrow mesenchymal stem cells served as the control group. The rat dorsal root ganglion neurons promoted the prolifera-tion of bone marrow mesenchymal stem cell-derived osteoblasts at 3 and 5 days of co-culture, as observed by lfuorescence microscopy. The levels of mRNAs for osteogenic differentiation-re-lated factors (including alkaline phosphatase, osteocalcin, osteopontin and bone morphogenetic protein 2) in the co-culture group were higher than those in the control group, as detected by real-time quantitative PCR. Our ifndings indicate that dorsal root ganglion neurons promote the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells, which pro-vides a theoretical basis forin vitro experiments aimed at constructing tissue-engineered bone.