Background: Paediatric allergic fungal rhinosinusitis is a subtype of chronic rhinosinusitis with significant focus in the paediatric population owing to early onset and difficulty managing through adult treatment options. Case Report: A 13-year-old male presented with nasal obstruction and facial deformity persisting for ten months. Examination revealed polypoidal tissue in both nasal cavities. Imaging showed involvement of all paranasal sinuses with tissue changes extending to the pons and compressing the frontal lobe. Endoscopic sinus surgery, coupled with steroids, cleared the disease. Histopathology and fungal cultures indicated allergic fungal rhinosinusitis. Post-surgery, nasal symptoms resolved, and after six months, facial deformity improved without need for further cosmetic interventions, leaving the parents satisfied. Conclusion: This case report highlights the need for early surgical intervention and monitored use of peri-operative steroids in paediatric AFRS.