Objectives: The purpose of this study is to analyze the prevalence of physical frailty and the socip-demographics, functionality and health factors associated with this syndrome in a sample of people with 100 and more years old. Methods: Data come from the ongoing population-based study, the Oporto Centenarian Study (PT100). Participants are people with 100 or more years old who lived in the Oporto Metropolitan Area (Portugal). The data collection was developed during 2013 and included demographic, social, health, functional, psychological (e.g. well-being) and cognitive domains. Phenotype frailty criteria assessment included exhaustion, weight loss, weakness, slowness and low activity. Descriptive analysis and binary logistic regression models were used for data analysis. Results: The final sample comprises 50 centenarians (mean age = 101.34, SD = 1.81; 84% female). From these, 4.0% were classified as "robust", 36.0% as "prefrail" and 60.0% as "frail". When analyzing the association between explanatory variables and frailty, only ADL showed a significant association with the frailty condition. A higher percentage of frail people were female (68.3%), lived in nursing homes (71.4%), were illiterate (71.9%) and had fair/poor subjective health (58.3%). Discussion: This study emphasizes the importance of physical frailty and its association with disability among the centenarian population. (C) 2014 Elsevier Masson SAS and European Union Geriatric Medicine Society. All rights reserved.