This study was designed to investigate the potential factors that influence the prevalence of the oral carriage of Candida species in patients with type II diabetes mellitus. One hundred and twenty-eight diabetic patients (68 males and 60 females, mean age 54 +/- 7 years) were sequentially enrolled along with 84 (44 males and 40 females mean age 52 +/- 8 years) healthy subjects. Samples were obtained by swabbing the oral mucosa of all participants. Yeast isolates were identified by germ tube test, with API 32 ID system, and by chlamydospore production on 'cornmeal' Tween-80 agar. Candida spp. was recovered from the oral cavity of 64% of the diabetic group, in contrast to 40% of the control group. Candida albicans was the most frequently isolated species in both groups. Potential etiologic factors such as xerostomia, dentures, age, gender and diabetes on oral carriage of Candida spp. were evaluated. The oral carriage of Candida spp. was significantly higher in 'diabetic' patients compared with the healthy subjects but it seems that parameters such as xerostomia, dentures, age, gender and glycemic control cannot be directly associated with Candida growth in the oral cavity in the presence of diabetes.