This study was carried out from October 2003 to March 2007 to investigate susceptibility patterns to antifungals of Candida strains isolated from 410 immunocompromised patients in Shiraz, Islamic Republic of Iran. Patients were checked for systemic candidiasis. Fungal colonization was determined and clinical samples collected from those patients with clinical signs of infections were examined. The carbohydrate assimilation patterns of all 354 isolates were studied. Susceptibility of the isolates to antifungal agents was determined using the reference broth microdilution method. Candida albicans was the species most often isolated. Voriconazole was highly active against all the isolates. Major resistance to itraconazole was observed in all Candida spp. Regular investigations into antifungal resistance in medical centres is highly recommended as this will result in more efficient management of invasive candidiasis in immunocompromised patients.