Rubus coreanus Miquel (RCM), one a type of edible red raspberry, grows wild in Korea and China and its unripe fruit has been used as a folk medicine for the treatment of impotence and as a diuretic agent. The goal of this study was to investigate the effects of RCM on the proliferation and differentiation of mouse osteoblast-like MC3T3-E1 cells. In this study, RCM extract (1-10 μg/mL) enhanced the viability of osteoblast cell. RCM extract also increased alkaline phosphatase (ALP) activity and osteocalcin secretion of MC3T3-E1 cells (significant at 1-10 μg/mL). Especially, at a concentration of 10 μg/mL ALP activity was increased by approximately 4.3 times in comparison with the control. Alizarin red staining and osteocalcin secretion assay showed that RCM extract stimulates differentiation of osteoblast cells by inducing the activation of mineralization. Moreover, reverse transcriptase polymerase chain reaction and western blotting assay indicated that RCM extract induced the differentiation at mRNA and protein level. These results suggest that RCM extract enhanced the osteoblast function by increasing the proliferation and differentiation of osteoblast like MC3T3-E1 cells.