Background Pulmonary fungal infection is one type of the common opportunistic infections in AIDS patients. The disease is hard to diagnose because of its complicated imaging features. The objective of this study was to investigate the imaging performance characteristics of pulmonary fungal infection in AIDS patients.Methods Fifty-one patients with AIDS complicated with pulmonary fungal infection and 56 patients of non-AIDS with pulmonary fungal infection were examined by CT scans and high-resolution CT scans. The contrast enhanced scans were performed in patients with the mass or suspected enlarged mediastinal lymph nodes. Results were compared between the two groups.Results The most common fungal infection in the two groups of patients was Candida albicans. The infection rates were 54.8% (28 cases) in the group (AIDS patients with pulmonary fungal infection) and 58.3% (32 cases) in another group (non-AIDS patients with pulmonary fungal infection). In the two groups, the difference in diffuse distribution and the difference in incidence of affected upper and lower lobes in the bilateral lung fields were statistically significant. The differences in patchy or large consolidation shadow, cavitas, enlarged lymph nodes in mediastinum and pleural effusion were also significant when comparing the two groups.Conclusions The lesion in most of AIDS patients with pulmonary fungal infection tends to exhibit diffuse distribution,patchy or large consolidation shadow covering a more extensive region. The differences between AIDS with pulmonary fungal infection and non-AIDS with pulmonary fungal infection are statistically significant in lesion location and complicated imaging features. The most common fungal infection in AIDS patients is Candida albicans.