miR-199b-5p is up-regulated significantly during the osteogenesis process in human bone marrow stromal cells (BMSCs). Inhibiting miR-199b-5p notably reduces while over-expressing miR-199b-5p promotes the BMSCs osteoblast differentiation, suggested by the alternations of osteogenic genes expression, ALP activity and the ARS-stained mineral nodules. miR-199b-5p exerts its role in BMSC osteogenesis most probably through the GSK-3 beta/beta-catenin signaling pathway. In conclusion, the present study revealed for the first time that miR-199b-5p plays a positive role in osteoblast differentiation. (C) 2016 The Authors. Published by Elsevier Inc.