Chronic granulomatous disease (CGD) is a primary immunodeficiency resulting from a disfunction of microbial capacity of phagocytes. Patients with this disease show great susceptibility to fungal and bacterial infections. Between 1988 and 1998, five paediatric patients with CGD who acquired mycotic infections were studied at the Paediatric Hospital Prof. Dr. J. P. Garrahan and their clinical and microbiological characteristics were described. The fungal infection appeared at the mean-age of 8.3 years (range: 1.1-17 years). All the patients had fever and lung involvement, three of them had suppurative abscesses of soft tissues. The mycological diagnosis was determined by microscopy, culture of clinical samples and serologic tests. There were three cases of disseminated aspergillosis, two cases of mixed infection: one due to Candida albicans and Nocardia asteroides and the other due to Scedosporium apiospermum and Cladosporium spp. Four out of the 5 patients died because of an infections process beyond control. Our conclusion is that new therapeutic measures must be considered along with the study of emerging pathogens in this group of patients.