Candida species causes oral candidiasis in immunosuppressed individuals such as cancer patients. This study aimed to determine the rate of candida infections in cancer patients (n= 150) and to identify different species of candida using Polymerase Chain Reaction-restriction fragment polymerase length polymorphism (PCR-RFLP), and to find the effect of candidiasis on the PH of the saliva in cancer patients (n=50) and controls (n=50) (Healthy individuals). The rate of candidiasis was different in patients with different types of cancer. A higher percentage of oral Candidiasis was observed in carcinoma (54 %), followed by leukemia patients (17.3 %), sarcoma type (15.3%), and lymphoma (13.33%). The highest prevalence of candidiasis was found in the old age group, 40-60years Candida albicans was the most common recorded species,70% in comparison to non-albicans species, followed by other species including: Candida glabrata (12%), Candida kefyr (6.7%), Candida tropicalis (5.3%), Candida krusei (3.3%), and Candida dubliniensis (2.7 %). The pH of saliva was more acidic in cancer patients who have candidiasis in comparison to control individuals (P-value 0.001). In conclusion, this study found that the rate of candidiasis is high among cancer patients and Candida albican is the most common species recorded in cancer patients.