Rheumatoid arthritis (RA) is an autoimmune disease that causes chronic inflammation of the joints affecting multiple organs in the body. Pericardial disease is a relative common systemic manifestation of RA. A small number of cases are described in the literature related to pericardial involvement in RA. We described a case of a 69 year-old-male with chronic RA who presented with progressively worsening shortness of breath at exertion. Previous echocardiogram performed one year ago had normal ejection fraction and no structural abnormalities. Laboratories showed no significant abnormalities. The echocardiogram and MRI performed at the time of evaluation, revealed a mass in the right ventricle free wall pericardia. On the pathology report the pericardial mass resection showed mild chronic inflammation, extensive fibrosis, fat necrosis and branchial cyst surrounded with mild chronic inflammation. After surgical resection the patient improved clinically.