Introduction: Peripheral T cell NHL (PTCL) and natural killer/T cell NHL (NKTCL) are relatively rare disorders. Data on clinical presentation, treatment and outcome are limited especially in older age groups. Methods: We identified 127 patients with PTCL and NKTCL, excluding cutaneous T/NK cell lymphoma, aged over 60 years old from Thailand nationwide multicenter registry. Results: Of 127 patients, median age of diagnosis was 67 years old. Patients aged older than 75 years old had similar characteristics to younger (60-74 years old) but higher comorbidity index. Seventy-nine patients (62.2%) received intensive/definite multi-agent chemotherapy, however, the proportion was significant lower in older patients (70.4% vs 34.5%, p b .001). After a median follow up duration of 17.3 months, 2-year progression free survival and overall survival were 38.1% and 48.5%. Univariate and multivariable analysis demonstrated older age, poor performance status and absence of definite multi-agent chemotherapy were associated with inferior survival. Definite multi-agent lymphoma specific chemotherapy was an independent factor for overall survival after adjustment for age, comorbidity index, performance status and prognostic index for T cell lymphoma. Conclusion: Despite overall poor prognosis of PTCL and NKTCL in older adults, chemotherapy could result in objective response and long-term survival in selected patients of this vulnerable age group thus emphasizing the importance of comprehensive geriatric evaluation.