Wilson-Mikity Syndrome, a form of chronic lung disease, is rarely developed with the widespread use of mechanical ventilaton. There has always been difficulty distinguishing it from bronchopulmonary dysplasia. The etiology and pathogenesis of this disease are still unknown. There are no reports in Korean literature about high-resolution (HR) CT follow-up of this disease. Diffuse interstitial thickening, which was noted on the initial examination, decreased, but some focal hyperinflations remained on follow-up HRCT. Further studies with HRCT will help to understand the progression of the disease, and will help to develop treatment and management programs.