This report describes 16 cases of candidiasis, seven of aspergillosis, four of mucormycosis, two of cryptococcosis and one of nocardiosis in which the kidney was involved. Characteristic patterns of renal tissue injury were seen in each of these infections. Candida and nocardia caused microabscesses in the cortex and medulla. Tissue destruction was minimal with candidiasis and when present was confined to the papillary tips and produced only mild impairment of renal function. Aspergillus and mucor invaded blood vessels resulting in thrombosis and extensive necrosis of cortical and medullary tissue and most patients had clinical and biochemical evidence of renal disease. Cryptococcosis caused no tissue reaction or clinically evident renal disease in the two immunosuppressed patients studied.