Background: Otomycosis has typically been described as fungal infection of the external auditory canal with infrequent complications involving the middle ear. Fungi causes 10% of all cases of otitis external Objective: To detect the most common causative fungi in immunocompetent and immunocompromised patients and the role of local treatment versus systemic treatment. Patients and method: This study is a prospective study. Among many patients presented in Al-Azher university hospitals, 125 patients were selected in this study. The patients were divided into two groups. Group A immunocompetent patients and group B immunocompromised patients. Results: The results of clinical feature show that the symptoms in the two groups was matched except the ear discharge was significantly higher in group B more than group A. The microbiological results of fungal infection show that the majority of microbiological findings was Aspergillus flavus in 13(29.5%) patients in group A and 27 (37.5%) patients in group B. Treatment used in the two studied groups, the first line of treatment was clearance of fungal mass, the local antifungal was used in 47 patients (94.0%) of the patients in group A, while only 3 patients was treated with systemic antifungal. In group B, 61 patients (81.3%) treated by local antifungal, while 14 patients (18.7%) treated by systemic antifungal. Conclusion: Otomycosis may affect both immunocompetent and immunocompromised patient, caused mainly by was Aspergillus flavus, standard of care is local antifungal however systemic antifungal may be used in selected patients especially those who are immunonocompromised