Pneumothorax, pneumomediastinum and pneumopericardium usually develop during emergency situations and these conditions may result in cardiopulmonary compromise, so an early and accurate diagnosis is seen as crucial for proper treatment. For diagnosis of pneumothorax, pneumomediastinum and pneumopericardium, chest radiography is a primary modality and CT can help for diagnosing them earlier and detecting associated abnormalities. The purpose of this pictorial essay is to describe the pathophysiology, various radiographic signs and diagnostic pitfalls of pneumothorax, pneumomediastinum and peumopericardium on chest radiographs that are correlated with CTs, and to aid the physician in the radiographic diagnosis.