In this review, we summarize the relevant pathways of circadian clock-controlled mitochondrial dynamics and discuss how the disruption of circadian clock and mitochondrial dynamics impact multiple etiologies of DCM, including insulin resistance, cardiac lipotoxicity, mitochondria-generated ROS, mitochondrial Ca2+ handling, MMP, mitophagy, and ER stress. This evidence concerns the gene CLOCK and familial dilated cardiomyopathy.