Peripheral blood stem cells (PBSC) are now routinely collected for use as hematopoietic support after high-dose chemotherapy for various malignancies. Nevertheless, few data are still available on PBSC collection in pediatric patients, owing to technical problems associated with the leukapheresis procedure in children. This paper briefly summarizes current knowledge about some technical aspects of pediatric leukapheresis for PBSC collection, according to the review of the literature and our personal experience on 60 procedures performed in 36 children affected with various malignancies. Technical issues include venous access, risk of volume shift due to exceeding extracorporeal circulation, and anticoagulation, that can induce severe side-effects. Moreover, criteria for optimizing the PBSC harvesting procedure in children, in particular the correct timing of leukapheresis, are discussed.