The aim of this study was to translate into Portuguese and to assess the reliability of an instrument for the diagnosis of diabetic distal polyneuropathy (DPN). The process for translation and adaptation into Portuguese of the Neuropathy Symptom Score (NSS) and the Neuropathy Disability Score (NDS) was performed following internationally standardized procedures. The instruments were applied by 2 raters in 57 consecutive subjects. Spearman correlation was used to evaluate the reliability and Cronbachs' alpha to evaluate the internal consistency of the items. Both, ECN and ESN, showed a good reliability (r= 0.77, p< 0.0001 and r= 0.76, p< 0.0001, respectively). ESN showed a good internal consistency (alpha= 0.74). The diagnosis of DPN, defined as the combination of the two scores (ECN+ESN) also showed a good reliability (r= 0.63, p< 0.0001). The Portuguese versions of the ESN and the ECN seem to be adequate for the diagnosis of DPN in this population.