Mucormycosis is an invasive fungal infection which arises due to immune compromised state of individuals.1 It is the second most common mucormycosis after aspergillosis caused by actinomucor, rhizopus, rhizomucor, and mucor species. The most important risk factor for mucormycosis development is malignant hematological disorders, bone marrow transplantation and prolonged corticosteroid administration in immunocompromised patient.2 Predisposing factors also includes malnutrition, prematurity, HIV infection and diabetes mellitus.3 The characteristics of mucor species infection is rapid vascular invasion followed by vascular thrombosis and tissue necrosis.4 The patients of leukemia having impaired immunity are more prone for mucormycosis infection.5 Usually, mucormycosis presents as an acute infection and manifests as rhinocerebral, pulmonary, gastrointestinal, cutaneous or disseminated forms.6 Immunosuppressive condition of the body rise the chance of opportunistic fungal infection.3 Uncontrolled invasive fungal infection can cause destruction of surrounding tissues and bone and, can cause exposure to external environment.5 Exposed maxillary bone can occur due to trauma, bacterial infection leading to osteomyelitis, viral infection like herpes zoster, fungal infection such as mucormycosis, and malignancies. Exposed maxillary bone may cause oro-antral communication and fistula which is an unusual communication between the oral cavity and the maxillary sinus. The aim is report a case of exposed maxillary bone due to mucormycosis in a nine year old child of acute lymphoblastic leukemia (ALL) for the dental consideration.