Forty samples of Karesh cheese were collected randomly from Cairo and Giza markets and examined for incidence of yeasts.All examined samples contained contaminating yeasts,High counts of yeasts being log 5.6 cfu/g were enumerated in the samples.Yeasts were isolated and identified.The results indicate that the Candida genus in the most frequently found organisms in cheese followed by Saccharomyces genus.Viability of Candida and Saccharomyces during the manufacture and storage of Kareish cheese supplemented with protective culture was studied.