© 2015.In this study, we aimed to determine the effect(s) of G-CSF priming on graft and transplantation parameters and compare these findings with those obtained without priming.A total of 64 pediatric patients transplanted from HLA-matched family donors were enrolled in the study. Twenty-nine patients received G-CSF primed marrow (G-BM group) and 35 patients received steady state bone marrow (S-BM group). Number of total nucleated cells (TNC) and CD34+ cells, CFU-GM colony number, neutrophil and platelet engraftment times, total length of stay in hospital, overall and disease free survival, and occasions of acute and chronic GvHD has been compared between these two groups.Granulocyte colony stimulating factor primed bone marrow (G-BM) yielded higher numbers of CD34+ cells, TNCs, and CFU-GM colony numbers compared to those obtained in S-BM. The neutrophil engraftment time, platelet engraftment time, length of stay in hospital, overall survival and disease free survival were not different between G-BM and S-BM groups. Also the cumulative incidence of grades II-IV acute and chronic GvHD were similar. It was observed that the use of G-CSF did not increase the risk of acute or chronic GvHD.We concluded that use of G-CSF for stem cell mobilization is an effective and safe method in children.