Recently, progression of disease within 24 months (POD24) has been demonstrated as a strong prognostic indicator in various types of malignant lymphoma. Peripheral T-cell lymphoma (PTCL) has an aggressive course and poor clinical outcomes. In this multicenter retrospective study, 111 consecutively registered patients with newly diagnosed PTCL were analyzed. Of these patients, 72 (64.9%) experienced POD24 (POD24 group), and the other 39 patients (35.1%) were analyzed as the no POD24 group. In the POD24 group, overall survival (OS) was significantly inferior to all patients, and in the no POD24 group, subsequent OS was significantly superior to the POD24 group, although the clinical characteristics between the POD24 group and no POD24 group were not significantly different. Twenty-three patients (20.7%) showed primary refractory disease to first-line therapy, and the prognosis was poor. The International Prognostic Index score and POD24 were identified as independent predictors in multivariate analysis for OS in all patients, and only performance status was an independent prognostic factor for OS in the POD24 group in multivariate analysis. In conclusion, the clinical significance of assessing POD24 in PTCL and the poor prognosis in patients with early disease progression were demonstrated.