Abstract： Objective To study the difference of gene expression profile of bone marrow mesenchymal stem cells （MSCs） cultured in vitro from coronary heart disease patient with or without diabetes mellitus by Affymetrix Gene array. Methods One male patient at age of 53 years with coronary heart disease and diabetes mellitus was included in this study with the diagnosis of coronary heart disease and type 2 diabetes mellitus. Another male patient at age of 51 years with coronary heart disease without diabetes mellitus was also included in this study with the diagnosis of coronary heart disease. MSCs of the two patients were isolated and purified by the methods of density gradient centrifugation with lymphocyte separation medium for human and adherent filtration. The MSCs expression profile of cytokines and signal transduction genes were examined by Affymetrix gene array. Results There were 27 functional protein genes expression in the patient with coronary heart disease and diabetes mellitus relating to cell apoptosis, cytokine, and signal transduction. Among them, the expression of 13 functional genes, including TNFRSF10B, TNFRSF21, NGF, CAV2, ITGA8, TNS1, ITGA2, AKT3, MBP, MAP2, INHBA, FST, PLA2G5, increased significantly in the patient with coronary heart disease and diabetes mellitus. However, the expression level of 14 genes, including EPR1, BIRC5, HELLS, BCL2, HGF, CASP1, SEPP1, ITGA9, MAP2K6, RUNX3, TGFBR2, RUNX2, CTNNB1, CDC42, decreased significantly. Conclusion The gene expression profile of bone marrow MSCs from coronary heart disease patient with diabetes mellitus is significantly different from the patient with coronary heart disease patient without diabetes mellitus.