Background: Candidiasis includes a range of opportunistic fungal diseases that appear in various forms such as oral thrush and stomatitis in the elderly. Recently, the resistance of Candida species to antibiotics selected to treat oral infections has increased significantly. Objectives: This study aimed to determine the antagonistic effects of probiotics on oral candidiasis in the elderly. Patients and Methods: Swab samples from the saliva and mouth of 72 elders residing in the elderly care centers in Gorgan were cultured in Sabouraud dextrose agar (SDA). The Candida spp. and Candida albicans were identified by culturing in CHROMagar Candida medium and using a PCR identification kit and API 20CAUX system. The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of nystatin and itraconazole based on the CLSI document. The well -diffusion method and the modified agar method were applied to separate dairy -isolated probiotics from cultures in MRS and M17 media and to study their antimicrobial effect. Results: Overall, 47 Candia isolates in seven different species were diagnosed. The MICs of itraconazole and nystatin were within