Pleural involvement secondary to Multiple Myeloma is considered a very rare complication. According to the literature only 1% of these patients develop a myelomatous pleural effusion. We present a case of a 39 year old man with multiple myeloma diagnosed six years prior to our evaluation, which developed progressive dyspnea, dry cough and right pleuritic chest pain two weeks prior to admission. On physical examination the patient had decreased breath sounds over the right posterior hemithorax accompanied by dullness to percussion. The chest radiogram was consistent with a right sided pleural effusion. Pleural fluid analysis revealed the presence of abundant abnormal plasma cells. The patient died four weeks after hospitalization. The presence of myelomatous pleural effusion is considered to be a poor prognostic finding, no matter at what disease stage it develops. So far no definite treatment has been shown to improve survival.