Epilepsy is one of the most severe neurological diseases that affect people around the globe. Self-rated health (SRH) refers to one’s subjective evaluation of their own health and is associated with various outcomes such as morbidity and mortality. Thus, understanding the association between epilepsy and SRH is of great importance. Moreover, SRH generally decreases with age. The aim of the current study is to test whether age moderates the link between epilepsy and SRH. The current study used a hierarchical regression and three multiple regressions to analyze the associations between epilepsy and SRH in 529 epilepsy patients and 46,978 healthy controls from the United Kingdom. The current study found that age significantly moderates the association between epilepsy and SRH. Specifically, epilepsy status was negatively related to SRH in young people (b = −0.69, p < 0.001, 95% C.I. [−0.84, −0.54]), more strongly in middle-aged adults (b = −0.81, p < 0.001, 95% C.I. [−0.95, −0.66]), and most strongly in older adults (b = −0.89, p < 0.001, 95% C.I. [−1.09, −0.69]). The current study may imply that older adults need more attention in terms of their SRH, which is closely associated with outcomes. Clinicians and health professionals should come up with ways that improve SRH in people with epilepsy, especially for older adults with epilepsy.