The invention discloses a method for promoting osteogenic differentiation of bone marrow mesenchymal stem cells. The method comprises the following steps of (1) culturing human bone marrow mesenchymalstem cells in a DMEM/F12 medium, and performing digestion with 0.25% pancreatin for passage when the cell fusion degree reaches 80-90%; and (2) inoculating a differential medium with the bone marrowmesenchymal stem cells obtained by subculture in the step (1), and carrying out induced differentiation, wherein the differential medium comprises the DMEM/F12 medium, 18-22 [mu]g/mL of insulin, 5-10ng/mL of dexamethasone, 40-50 [mu]g/mL of ascorbic acid, 15-23 [mu]g/mL of sulfobutyl-beta-cyclodextrin, 45-52 [mu]g/mL of betaine, 10-15 ng/mL of indium acetate and 50-60 [mu]g/mL of glutathione. According to the invention, the differential medium is inoculated with the bone marrow mesenchymal stem cells obtained through subculture, and the sulfobutyl-beta-cyclodextrin, the betaine and the indiumacetate are added into the differential medium to achieve a synergistic effect, so that the osteogenic differentiation efficiency of the bone marrow mesenchymal stem cells is effectively improved, the osteogenic differentiation time is shortened, and a guarantee is provided for clinical application of the bone marrow mesenchymal stem cells to tissue-engineered bone construction.