Tuberculosis and aspergillosis are two of the most common chronic lung infections that occur in children. They both present in a variety of ways, acutely or insidiously. Tuberculosis is increasing in incidence due to increased immigration and the HIV pandemic. Symptoms can range from subclinical to acute sepsis with respiratory distress requiring intensive care support. Aspergillus is an important pathogen, particularly in patients who are immunocompromised either due to organ impairment such as cystic fibrosis or due to primary or secondary suppression of the immune system. Aspergillosis can also present with mild to fulminant symptomatology. Imaging is often the cornerstone of diagnosis. This article concentrates on the wide range of radiological features that these two organisms can cause.