Coronary artery disease (CAD) is a serious global problem that has been considered to be a major cause of death. Circular RNAs (circRNAs) as a key player in the regulation of cardiac progression and disease. Nevertheless, most circRNAs are poorly understood. In our research, we discussed the circ_TET3 (circ_0006251) function in the development of CAD. Firstly, circ_0006251 expression was measured through RT-qPCR analysis. Functional results prove the clear functionality of circ_0006251 for CAD. In addition, mechanism experiments including RIP, RNA pull-down and luciferase reporter results were applied to delve into the mechanisms of regulation of circ_0006251 in CAD. Results showed that Circ_0006251 expression was notably increased in PDGF-BB-induced VSMCs cells. Moreover, circ_0006251 interference mitigated the VSMCs cells proliferation and stimulated apoptosis after being treated with PDGF-BB. Furthermore, circ_0006251 targeted TET3 and PPM1B via sponging miR-361-3p, thereby contributing to CAD occurrence. In conclusion, Circ_0006251 could be identified as a biomarker for CAD which might shed light on the diagnosis and therapy of CAD.