Circular RNAs (circRNAs) are non‑coding RNAs that are found in the cytoplasm or stored in the exosomes, where they are not affected by RNA exonucleases. CircRNAs are widely expressed in mammalian tissues and cells. A number of studies have suggested that circRNAs are associated with the physiology and pathology of cardiovascular diseases (CVDs). Therefore, circRNAs have been considered as effector molecules and biomarkers in the cardiovascular system. The present review article summarizes the biological origin and roles of circRNAs as well as the available databases and research methods for their identification. Furthermore, it describes their regulatory mechanisms in cardiovascular physiology and pathology, including the regulation of atherosclerosis, immunity, cell proliferation, apoptosis and autophagy. In addition, the current review discusses the unresolved problems in circRNA research and the application of circRNAs in the treatment of CVDs. Finally, the CVD‑associated circRNAs are also reviewed.