Currently, haploidentical hematopoietic cell transplantation (HHCT) is considered an established option for patients who have diseases curable with hematopoietic cell transplantation (HCT) but who lack a suitable donor. We report the results of a prospective study to evaluate the feasibility and efficacy of ex vivo T cell-depleted (TCD) HHCT for children with acute myeloid leumekia (AML). Twenty-nine patients with AML received TCD HHCT at Asan Medical Center Children’s Hospital between July 2008 and May 2017. Six received CD3-depleted HHCT (CD3-HHCT) and 23 received TCRαβ-depleted graft (TCRαβ-HHCT). Among 29 patients, 12 were in CR1, 7 in CR2 and 10 in non-CR. Six patients had relapsed after previous allogeneic HCT. Risk groups of patients were classified as high-risk (HR; patients with relapsed/refractory disease, or relapse after HCT) and low-risk (LR; patients in CR without any of the HR feature). Of the 29 patients, 16 were LR and 13 were HR. The median age at HHCT was 11 years (range, 1-19). All 29 patients achieved neutrophil engraftment at a median of 10 days (range, 9-17) post-HHCT. None experienced graft rejection. The cumulative incidence (CI) of acute GVHD grade II-IV and III-IV were 28.4% and 14.8%, respectively. Two of 26 evaluable patients developed extensive chronic GVHD with a CI of 8.6%. As of August 20, 2017, 19 of the 29 patients survived free of disease with a median follow-up of 12.1 months (range, 1.17-111.20 months). Causes of death of 9 patients were relapse (n=7), comorbid moyamoya disease (n=1) and disseminated tuberculosis (n=1), leading to treatment-related mortality (TRM) of 10.3%. The Kaplan-Meier estimated EFS and OS for all patients were 58.9% and 65.3%, respectively. The EFS for 10 patients with relapsed/refractory disease at the time of HHCT was worse than that for the remaining 19 patients (18.8% vs 76.7%, P=0.004). In addition, the outcome for 6 patients who had received previous allogeneic transplant was poor with EFS of 33.3%. According to risk groups, patients of LR had a significantly better survival than those of HR (86.2% vs 24.6%, P=0.001). In this study, HHCT using ex vivo T-cell depleted grafts showed a favorable outcome for pediatric patients with hematologic malignancy in CR. However, further study is warranted to improve the outcome for patients with relapsed and refractory malignant disease.