Oral candidiasis is a common opportunistic fungal infection frequently observed in immunocompromised individuals. This retrospective study aimed to evaluate the prevalence and identify significant risk factors associated with oral candidiasis in patients with compromised immune status. Medical records of 500 immunocompromised patients from a tertiary care hospital over five years were reviewed. Data collected included demographic details, underlying immunosuppressive conditions, medication history, oral hygiene status, and clinical presentations of candidiasis. The overall prevalence of oral candidiasis was found to be 32%, with higher rates among patients with HIV/AIDS, those undergoing chemotherapy, and transplant recipients on immunosuppressive therapy. Key risk factors significantly associated with oral candidiasis included low CD4+ T-cell counts, prolonged antibiotic and corticosteroid use, xerostomia, and poor oral hygiene. The study highlights the importance of early diagnosis and targeted preventive strategies in high-risk groups to reduce morbidity related to oral fungal infections. Future prospective studies are recommended to better understand causal relationships and improve management protocols.