Objective To study the clinical features and prognosis of tumor lysis syndrome (TLS) in children and provide clinical guidance for the prevention and treatment of TLS. Methods The clinical data of patients with TLS from December 2014 to March 2023 were retrospectively analyzed for their clinical features and prognosis. Results A total of 38 children with TLS were included, 27 males and 11 females, with a median age of 6.6 (2.9-9.9) years.. Among these children, 18 were diagnosed with acute lymphoblastic leukemia, 8 with acute myeloid leukemia, and 12 with Burkitt lymphoma, of which 12 cases (31.6 %) were combined with renal infiltration. 37 cases (97.4 %) developed TLS from 24 hours before chemotherapy to 72 hours after the start of chemotherapy, 21 cases were consistent with clinical TLS, and 17 cases with laboratory TLS. The main manifestations of TLS were acute kidney injury (AKI, 20 cases), nausea and vomiting (18 cases), fever (18 cases), chest tightness, and hypoxemia (12 cases). 21 children were transferred to the PICU for treatment of disease exacerbation, and a total of 3 TLS-related deaths occurred. Uric acid was lowered by allopurinol in 16 cases and by recombinant uric acid oxidase in 22 cases. Compared with the allopurinol group, the recombinant uric acid oxidase group had a higher proportion of laboratory TLS and a lower incidence of AKI and severe transfer to the PICU, with statistically significant differences (P<0.05). The LDH and uric acid levels in the allopurinol group were higher at the five time points of -3 d before the onset of TLS, the same day of TLS, and +1 d, +3 d, and +5 d after TLS, and the levels in the allopurinol group were higher at the five time points of -1 d, +1 d, +3 d, and +5 d after TLS. The difference between the LDH, uric acid and blood creatinine levels in the recombinant uric acid oxidase group was statistically significant (P<0.05). The uric acid levels in the recombinant uric acid oxidase group were lower than those in the allopurinol group at +1 d, +3 d and +5 d after the onset of TLS, and the difference was statistically significant (P<0.05). Conclusion Patients with high-load hematological tumors have a high risk of TLS at the early stage of treatment, and uric acid oxidase can effectively lower uric acid, reduce the occurrence of AKI, lower the rate of severe disease, and shorten the duration of TLS.