CD19 chimeric antigen receptor T (CAR-T) cell therapy represents an effective approach to treating patients with relapsed or refractory B-cell hematologic malignancies. Nevertheless, owing to the immunosuppressive effects of this regimen, patients undergoing CD19 CAR-T cell therapy may face an elevated risk of invasive fungal infections, which involve fungi penetrating the host's tissues or bloodstream, leading to life-threating infectious diseases. Herein, we present the case of a 17-year-old male diagnosed with acute lymphoblastic leukemia, who subsequently experienced a fatal invasive fungal infection following administration of CAR-T cell therapy. Furthermore, we delve into the identification of risk factors, implementation of preventive measures and exploration of therapeutic interventions for invasive fungal infections after CAR-T cell therapy.