The application of apheresis equipment to perform leukapheresis (LK) in low weight paediatric patients is logistically complex and lacking of largest clinical performing experiences, meanwhile, the benefit from LK is controversial. In this study, 15 children with acute lymphoblastic leukemia(ALL)and acute myeloid leukemia (AML) and hyperleukocytosis were treated with the COBE Spectra apheresis system in the general paediatric ward by the staff from the department of Blood Transfusion. 26 LK procedures were performed. 12 patients (80%) were performed with peripheral veins, others (20%) with femoral veins. Median age, body weight of the patients was 4 years (range from1 year 10 month to 7 years) and 15 kg (range from10 to 20 kg). The median white blood cell (WBC) count of pre-first-LK was 289 × 10 9 /L (range from 108 × 10 9 /L to 579 × 10 9 /L). The median decrease in WBC count after each LK was 34% (range from 14% to 54%), and overall decrease in WBC after completion of LK procedures was 45% (range from 15% to 70%). All of the patients had no further signs of leukostasis and achieved marked reductions in WBC counts. Only minor clinical adverse events were attributable to LK. With adequate monitoring and experienced team, LK is a safe and may be a beneficial leukoreduction method in small patients weighing 20 kg or less with ALL and AML. [ABSTRACT FROM AUTHOR]