With a variety of aetiologies and clinical presentations, Dilated Cardiomyopathy (DCM) presents considerable hurdles for both diagnosis and treatment. Cardiac magnetic resonance imaging (CMR) has become a useful diagnostic technique for DCM, providing information on the anatomy, physiology, and tissue properties of the heart. Using both well-established and recently developed CMR techniques, this review investigates the function of CMR in the diagnosis and treatment of idiopathic DCM. Using reliable databases, a thorough search of the literature was carried out with an emphasis on papers released between 2014 and 2024. English-language literature examining the clinical uses of CMR in idiopathic DCM were included in the inclusion criteria. A vital component of the assessment of dilated cardiomyopathy (DCM) is cardiac magnetic resonance imaging (CMR), which provides thorough insights into the anatomy and function of the heart. Precise evaluation of tissue properties, ventricular function, and cardiac shape is made possible by CMR, which helps DCM patients get an accurate diagnosis and risk assessment. The use of advanced CMR methods, such as T1 mapping and late gadolinium enhancement (LGE) imaging, yields significant insights into the underlying aetiologies and myocardial fibrosis. Furthermore, customized prognostic evaluations are provided by CMR-based risk stratification algorithms that include many factors, improving clinical decision-making in DCM treatment. Continuous developments are expected to improve prognostic utility and accuracy, which will need efforts to lower prices and increase accessibility in order to achieve better patient outcomes and wider clinical usage