Eucommia ulmoidesis one of the popular tonic herbs for the treatment of low back pain and bone fracture and is used in Korean medicine to reinforce muscles and bones. This study was performed to investigate the effects ofE. ulmoidesextract on longitudinal bone growth rate, growth plate height, and the expressions of bone morphogenetic protein 2 (BMP-2) and insulin-like growth factor 1 (IGF-1) in adolescent female rats. In two groups, we administered a twice-daily dosage ofE. ulmoidesextract (at 30 and 100 mg/kg, respectively)per osover 4 days, and in a control group, we administered vehicle only under the same conditions. Longitudinal bone growth rate in newly synthesized bone was observed using tetracycline labeling. Chondrocyte proliferation in the growth plate was observed using cresyl violet dye. In addition, we analyzed the expressions of BMP-2 and IGF-1 using immunohistochemistry.Eucommia ulmoidesextract significantly increased longitudinal bone growth rate and growth plate height in adolescent female rats. In the immunohistochemical study,E. ulmoidesmarkedly increased BMP-2 and IGF-1 expressions in the proliferative and hypertrophic zones. In conclusion,E. ulmoidesincreased longitudinal bone growth rate by promoting chondrogenesis in the growth plate and the levels of BMP-2 and IGF-1.Eucommia ulmoidescould be helpful for increasing bone growth in children who have growth retardation. Copyright © 2014 John Wiley & Sons, Ltd.