In the present study a total of 50 samples of poultry ration and drinking water in front of the birds (25 for each) were collected from various private broiler farms at Giza governorate. The collected samples were subjected to isolation and identification of contaminant fungi, screening of poultry feeds for aflatoxin B1 residues, assessment of isolated A. flavus strains for aflatoxin production as well as molecular detection of the aflR gene in isolated A. flavus strains by polymerase chain reaction and molecular detection of the pathogenic Candida species. The results showed 100 rations samples were highly contaminated with moulds, but were free from yeasts. The prevalence of mould and yeast from drinking water samples were 48% and 88%, respectively. The total mould count (log 10 CFU/g) obtained from poultry feed samples collected from poultry houses was higher than that of drinking water samples. Total mould count (log 10 CFU/g) in poultry feed samples ranged from 1.8 to 4.4 (log 10 cfu/g) while in drinking water samples ranged from 1 to 1.8 (log 10 cfu/ml).On the other side , it was found that the total yeast count of the examined drinking water ranged from 1.8 and 4. 2 (log 10 cfu/ml). Altogether, one hundred and three isolates representing 9 genera were recovered during this study. The most frequent fungi were from the genus Aspergillus, were A. flavus (17.9 %) appeared to be the most prevalent.