Background Peripheral T-cell lymphoma ( PTCL) is rare non-Hodgkin lymphoma (NHL) which is usually associated with an inferior outcome to those of B-cell lymphomas. We report our institutional experience over an 18-year period. Methods In this study, we retrospectively investigated 19 cases of PTCL diagnosed at the Asan Medical Center from October 1995 to April 2014. The clinical characteristics, treatment results, and outcomes were reviewed. Those with isolated cutaneous T-cell lymphoma and anaplastic large cell lymphoma were excluded from this analysis. Results According to the World Health Organization (WHO) PTCL classification, 10 patients had PTCL, not otherwise specified ( PTCL-NOS), 7 had extranodal natural killer/T-cell lymphoma, nasal type (ENKL), 1 had subcutaneous panniculitis-like T-cell lymphoma and 1 had angioimmunoblastic T-cell lymphoma. Patients were treated with various chemotherapeutic regimens. Two patients with PTCL-NOS underwent allogeneic hematopoietic stem cell transplantation (HSCT) and autologous HSCT, respectively, and 1 with ENKL underwent autologous HSCT. Of the 19 patients, 7(36.8%) died from disease progression, and there was no treatment-related mortality. The 5-year overall and event-free survival rates were 73.7% and 50.0% in all cases, 80.0% and 56.1% in PTCL-NOS, and, 71.4% and 28.6% in ENKL, respectively. Conclusion Although children with PTCL experienced frequent relapse, many of them could be rescued by salvage treatment, resulting in comparable overall survival outcomes to other NHL. Multicenter trials are required to refine the prognostic factors in PTCL and further confirm the outcome of PTCL in Korea. Furthermore, an effort should be made to develop more efficient initial therapies through collaborative research to improve outcomes.