Aims: To investigate the prevalence of oral candida species in patients with head and neck cancer before and after radiation therapy. Material and Methods: A total of 219 subjects was screened initially.180 patients were lost for follow-up due to peak Covid -19 pandemic. Thirty- nine subjects who received radiation therapy (RT) for the treatment of head and neck cancer were examined for signs of oral candidiasis before and one month after the treatment. The stimulated saliva was collected from the subjects in a sterile bottle. The samples were plated onto the HiChrome agar for Candida. The inoculated plates were incubated at 37ºC for 48 hours. The species was the identified by seeing the color of the colonies grown in Chrom Agar. Mucositis and dysphagia were also evaluated in each subject and their association with candidiasis were also analyzed. Results: Among the thirty-nine samples studied Candida was present in 53.8% of cases pre and 69.2% post treatment respectively. C. albicans (35.9%) was the predominant isolate followed by C. krusei (23.1%) and in the second visit. Eventhough there was an increase in C. albicans (53.8%), C. kruseui (28.2%), two more variants (C. tropicalis and C. mucor) were present. Subjects were also graded for mucositis and dysphagia; it was found that most of them had grade 1 mucositis (61.5%) and it was noted that higher proportion of the candida (70%) was found in the second visit. While grading dysphagia majority had grade 2(35.9%) and grade 2 dysphagia showed highest percentage having Candida (40.7%). Conclusion: The study revealed an increase incidence of Candida species in saliva in the patients who are undergoing radiotherapy for oral cancer. At the end of radiotherapy there was an increase in the growth of Candida-albicans species and non - albicans candida. Clinical Significance: Although all forms of candida are closely related they differ in antifungal susceptibility patterns. Candida Species identification through antifungal susceptibility testing is essential for selecting the appropriate medication and predicting the treatment outcome.