IntroductionHematological malignancies (HMs) are a group of malignant clonal disorders that mainly affect the blood and hematopoietic tissues. They are broadly categorized into myeloid and lymphoid lineages \RL (1)\RL. Acute lymphoblastic leukemia (ALL) is classified as acute \RL lymphoid lineage disorder. All hematological malignancies engage the immune system and raise the chances of opportunistic infections mainly invasive fungal infections \RL)IFIs\RL( (2).Aspergillus and Mucorales species are emerged as increasingly relevant and most common agents responsible for highly lethal IFIs (3). The implementation of prophylaxis targetingCandida species in individuals with HMs has resulted in a higher occurrence of Aspergillosis compared to Candida infections (4).Aspergillus spp., the airborne microorganisms, can manifest in three principal forms: invasive, saprophytic, and allergic (5). AlthoughAspergillus fumigatus (A. fumigatus ) is the predominant species associated with disease, other species can also result in invasive infections in profound immunocompromised patients (6). Statistics indicate that invasive aspergillosis occurs in 4-15% of cases and has a mortality rate between 60% and 85% (7). Mucormycosis, a less frequent occurrence compared to aspergillosis, is a devastatingly angioinvasive fungal infection caused by ubiquitous filamentous fungi belonging to the Mucorales order (8). The main damage is rhino-orbital-cerebral, pulmonary, gastrointestinal, cutaneous, and disseminated, with a high mortality rate, estimated between 32% and 70% (9). Although lung is the most prevalent site of infection in patients with hematologic malignancies, rhino-orbito-cerebral mucormycosis (ROCM) is the most common form classically described in diabetic patients (10).Severe neutropenia (absolute neutrophil count below 500 cells/mm3) due to toxic antineoplastic chemotherapies and myelosuppressive agents or allogeneic hematopoietic stem cell transplantation (allo-HSCT) placing HMs at a higher risk of evolving life-threatening infections with few symptoms (11).Herein we report a case of concomitant acute invasive fungal rhinosinusitis (AIFR) and invasive pulmonary fungal infection withAspergillus and Mucoraceae species in a patient with pre B cell ALL. This research was approved by the Ethics committee of Isfahan University of medical sciences (IR.ARI.MUI.REC.1403.094), and written informed consent was obtained from the patient.