Abstract: OBJECTIVE To explore the role of clinical pharmacists in the treatment of a pediatric patient with acute lymphoblastic leukemia(ALL) undergoing chimeric antigen receptor T-cell immunotherapy(CAR-T), and to provide reference for pharmaceutical care of subsequent cases. METHODS A clinical pharmacist participated in the diagnosis and treatment process of a pediatric patient with ALL receiving CAR-T immunotherapy. Based on consensus guidelines for the management of CAR-T therapy-related toxicities and antimicrobial stewardship protocols for children, the clinical pharmacist provided comprehensive pharmaceutical care throughout the entire treatment course. The key interventions included: identification, grading, and monitoring of cytokine release syndrome(CRS) following CAR-T infusion, as well as oversight of therapeutic agents used; identification and prevention of CAR-T cell-related encephalopathy syndrome(CRES); identification of coagulation disorders and recommendation for anticoagulation therapy; and refined antimicrobial stewardship with ongoing assessment throughout the treatment. RESULTS The clinical physician adopted the clinical pharmacist's recommendations. The patient's CRS was effectively controlled, with body temperature returning to normal; symptoms including headache and rash improved; coagulation function recovered; and infection was effectively prevented and managed. The patient was discharged in stable condition on day 22 after CAR-T infusion. CONCLUSION Clinical pharmacists, through participation in comprehensive pharmaceutical care for pediatric patients undergoing CAR-T immunotherapy, assisted physicians in optimizing treatment regimens and ensured the efficacy and safety of medication in pediatric patients.