Apart from serologic markers structural changes of bronchi and adjacent lung tissue are key factors determining the diagnosis and course of allergic bronchopulmonary aspergillosis (ABPA). Due to problems relating to procedural hazards and radiation exposure using bronchography and computerized tomography we evaluated the efficacy of magnetic resonance imaging of the lung in ABPA. Direct comparison of high resolution computerized tomography (HR-CT) and magnetic resonance imaging (MR) in 5 patients with ABPA revealed that image resolution and data acquisition of present MR technique are insufficient to accurately delineate the extent and activity of structural damage of bronchi and adjacent lung tissue. Although major bronchiectasis may be identified, MR was unable to demonstrate even extensive patchy infiltrates seen in high resolution computerized tomography. At present, magnetic resonance imaging cannot be recommended for determining diagnosis or course of ABPA.