Abstract: Objective To evaluate the value of cardiac magnetic resonance imaging (CMR) in the diagnosis and treatment of ventricular arrhythmia. Methods Total 45 patients with ventricular arrhythmias from January 2016 to January 2017 were selected as subjects. All subjects underwent first pass perfusion and delayed scan analysis (LEG) to record the information of cardiac structure, cardiac function and myocardial ischemia. The left ventricular end diastolic diameter, left ventricular systolic area, left ventricular septal thickness, left ventricular posterior wall thickness, left ventricular ejection fraction and right ventricular ejection fraction were recorded. The results were compared with those of echocardiography (UCG) and coronary angiography (CAG). Results Left ventricular end-diastolic diameter, left ventricular systolic area, left ventricular septal thickness, left ventricular posterior wall thickness, left ventricular ejection fraction and right ventricular ejection fraction measured by CMR were positively correlated with UCG. There was no significant difference in left ventricular structure and function evaluation between the two groups (P>0.05). There were 10 cases of right ventricular enlargement and 16 cases of right ventricular systolic dysfunction, while none of the UCG cases were detected. There was no significant difference in the detection of myocardial ischemia between CMR and UCG in different coronary lesions (P>0.05), but the detection rate of myocardial ischemia by CMR was higher than that by UCG in different degree of coronary stenosis. Conclusion CMR has a stronger ability to differentiate the right ventricular physiological structure lesions in patients with ventricular arrhythmia, and has a higher detection rate of myocardial ischemia in patients with different degree of coronary artery stenosis. CMR has a higher application value in the diagnosis and treatment of ventricular arrhythmia, and is worthy of clinical application.