Associations between telomere length and various chronic diseases associated with ageing have led to the suggestion that telomere length may be an ageing biomarker. At the clinical level, the suggestion of using measurements of frailty as a measure of biological ageing has also been suggested. This study examines the hypothesis that telomere shortening may form the biological basis for frailty, using data obtained from a health survey of 2000 men and women aged 65 years and over, living in the community, and followed up for 4 years to determine survival. Frailty was measured using the frailty index, a summation of deficits covering physical, psychological, and functional domains. Telomere length was measured in 976 men and 1030 women, using real-time quantitative polymerase chain reaction. Women were more frail than men but had longer telomere length. In men only, there was a negative association between telomere length and age and a positive association between frailty index and mortality after adjusting for age. There was no correlation between telomere length and frailty index in either sex. While telomere length may be a biomarker of cellular senescence, this relationship may not be extrapolated to the functional level represented by the frailty phenotype.