Background: Pericardial disease is an important cause of morbidity and mortality in patients with cardiovascular disease. Although the pericardium is usually sufficiently thick to be identified on CCT and CMR, visualization at the most common site of pericardial defects, the lateral, posterior, and inferior left ventricular wall, can be poor because of a paucity of fat. Objective: The aim of this study was to evaluate the role of CT & MRI in the diagnosis of pericardial diseases. Patients and Methods: 30 patients with cardiac abnormalities were included. All patients' data of preoperative were reported. Range of age was 15-59 years. 20 patients were male and 10 patients were female. Results: In our study MR imaging showed accuracy of 93% for differentiation between constrictive pericarditis and restrictive cardiomyopathy on the basis of depiction of thickened pericardium. In our study on MR images, an intact pericardial line may be observed if an adjacent tumor extends to the pericardium but not through it. Tumors that have invaded the pericardium may be recognized by focal obliteration of the pericardial line and the presence of pericardial effusion. Hemorrhagic pericardial effusions secondary to metastases usually have high signal intensity on SE images. Conclusion: CT and MR imaging should be used when findings at echocardiography are difficult to interpret or conflict with clinical findings.