Objectives: Metabolic syndrome (MetS) is a risk factor for cardiovascular disease, diabetes, and all-cause mortality. Frailty is a condition of decreased multi-system physiological reserve where one has increased vulnerability to stressors. This study aimed to examine if MetS is associated with prevalent and incident frailty over a 4-year follow-up period in an aged population. Methods: This study used data from waves 1 (2009–2011) and 3 (2014–2015) of The Irish Longitudinal Study on Ageing. Those aged 5100), showed MetS was associated with prevalent frailty as assessed by both FP (odds ratio (OR) 1.29, p