Inflammatory pseudotumor is the most frequent primary lung tumor in children under the age of 16. Clinical history and radiological diagnosis are often non-specific, making diagnosis uneasy. In some instances, only surgery can provide a definite diagnosis. However, when dealing with a solitary mass of the lung in an infant the radiologists should always include inflammatory pseudotumor among the entities of the differential diagnosis. This case report discusses the radiological features of inflammatory pseudotumors.