OBJECTIVE To analyze the treating efficacy of meropenem on blood tumor combined with the infection in children. METHODS A retrospective study protocol was adopted,totally 80 acute leukemia and other subjects complicated with infection were observed.The dosage of meropenem was 10-20 mg/kg,q8-12 h for all the patients and the treatment course in most patients was less than 10-14 days. RESULTS The effectiveness rate was 78.8%.The effectiveness rate was 80% for hematological system diseases complicated with septicemia and was 77.0% for hematological system diseases complicated with agranulocytosis.The occurrence rate of side effect of meropenem in this group was 0. CONCLUSIONS Meropenem is significantly effective and safe in the treatment of hematological system diseases complicated with infections.