Type 2 diabetes mellitus is a chronic disorder with growing prevalence in the world. Patients with T2DM suffer from complications which lead to mortality. Coronary artery disease (CAD) is a chronic complication of T2DM which develops in about 60% of patients with T2DM and increase the risk of heart attack. The quest for biomarkers to identify T2DM patients with CAD in early stages has received major interest in recent years. This study aims to find differentially expressed genes in peripheral bloods of T2DM patients versus CAD patients to introduce CAD-specific candidate biomarkers. The gene expression datasets of GSE26168 (T2DM patients) and GSE23561 (patients with CAD) were utilized in bioinformatics analysis. The analysis was carried out by GEO2R. The adjusted P value 0.05 and log fold change (FC)?>?2.0 or log FC???2.0 were used as the cut-off criteria. Venn diagram was drawn to remove common differentially expressed genes in both groups and find CAD-specific genes. Gene ontology enrichment analysis was performed on target gene list by submitting to PANTHER (http://pantherdb.org/). 78 CAD-specific genes were found which their expression were not influenced by T2DM. LOC401330 and HBII-437 were the most down- and up-regulated transcripts in CAD patients respectively. Gene ontology and pathway enrichment analysis showed that inflammatory pathway contained the highest number of genes including ARP2/3, ACTB, NFATC4 and PLCB3. Taken together, these genes and pathways provide a new perspective for introducing novel biomarker to identify T2DM patients with CAD