Mediastinal compression syndrome is a commonly seen entity. Mediastinal compression, mostly due to a space-occupying lesion, is distinct and different from mediastinitis/mediastinal fibrosis, which could also lead to superior vena cava syndrome. Idiopathic mediastinal fibrosis should also be considered as differential diagnosis of mediastinal structures with various radiological, CT and MRI and histological features if feasible. Medical therapy is disappointing while surgical cure has limitations. This interesting patient presented as mediastinal compression syndrome, which on investigation was postulated as idiopathic mediastinal fibrosis, as a diagnosis on exclusion of other causes, which is rare, hence is being reported.