Background: Pediatric patients with hematologic malignancies are susceptible to invasive mould sinusitis (IMS). IMS is a rare entity that requires careful attention and prompts management due to its high mortality. Methods: This is a retrospective analysis of pediatric patients with hematological malignancies treated at Children Cancer Hospital Egypt through the period from 2008 till 2016 with proven IMS. Results: Thirty-four patients were diagnosed with IMS. Five 5(15%) patients had an invasive rhino-cerebral fungal disease. Mucormycosis were isolated in 17(50%) patients, Aspergillosis in 13 (38%) patients, and mixed fungal in 4 (12%) patients. Sinuses were the only localized site in (45%). Extra-nasal spread was reported in 20 patients; Sino-pulmonary in 12(35%), Sino-cerebral in 5(15%), and Sino-orbital in 2(5%) patients. Combined antifungal therapy with surgical debridement was done in 59% of patients with a better outcome when compared to those who received only medical antifungal treatment (P = 0.01). The overall mortality rate at week 12 was 35% (12 patients), and IMS attributable mortality was 20% (7 patients). IMS with cerebral extension carried the highest mortality rate for both 12-week all-cause (p=0.04) and fungal-attributable (P=0.01) mortality. Conclusions: Pediatric patients with hematologic malignancies are susceptible to invasive mould sinusitis (IMS). Surgical debridement, combined with antifungal therapy, improves outcomes among those patients. IMS patients with cerebral extension had a higher risk of mortality.