Cognitive performance is known to decline in the aging organism as also in chronic epileptic disease. However, little is known about cognitive function in the aged epileptic animal. In the present study, one-month-old rats first experienced a sustained pilocarpine-induced status epilepticus and were further tested at different ages. Field potential recordings to study long-term potentiation (LTP) as well as behavioral learning tests in the Morris water maze were performed in three-month-old rats (young group) and in 16–18-month-old rats (aged group), respectively. In the hidden platform task in the Morris water maze, pilocarpine-treated rats showed significantly higher escape latencies compared to controls in both the young and the aged groups. Moreover, aged controls showed significantly worse performance than young controls. On the other hand, there was no significant difference between young and aged pilocarpine-treated rats. The impaired performance in the Morris water maze was largely paralleled by altered LTP induced by high-frequency stimulation (100 Hz, 1 s) applied to Schaffer collaterals in the hippocampal CA1 region. Thus, LTP was reduced in pilocarpine-treated rats compared to controls in both the young and the aged groups. Interestingly, aged controls showed higher LTP levels than young controls, and within the group of pilocarpine-treated rats, the aged animals exhibited more LTP than the young ones. Our results confirm that both aging and chronic epilepsy can lead to persistent changes in the propensity to express LTP as well as to an altered learning behavior.