OBJECTIVE: To determine the trajectory of cognitive decline before and after incident stroke. METHODS: By using data from the English Longitudinal Study of Ageing, we studied 9,278 participants without dementia with no history of stroke who underwent cognitive assessment at baseline (wave 1) and at least 1 other time point (waves 2-7). We used linear mixed models to analyze repeated measures and longitudinal data. RESULTS: Among the 9,278 participants (56.8% women, mean age 63.1 ± 10.3 years), 471 (5.1%) incident stroke events were identified. Compared with stroke-free participants, multivariable-adjusted rates of prestroke cognitive decline in global cognition, memory, semantic fluency, and temporal orientation of participants who later experienced an incident stroke were increased by -0.029 , -0.016, -0.022, and -0.024 SD/y, respectively. Among the 471 stroke survivors, the multivariable-adjusted acute changes in the 4 cognitive domains were -0.257, -0.150, -0.121, and -0.272 SD, respectively. In the years after stroke, global cognition declined over time and was steeper than its prestroke slope, that is, by -0.064 SD/y after multivariable adjustment. The rates of memory, semantic fluency, and temporal orientation decline were -0.046, -0.033, and -0.037 SD/y, respectively. CONCLUSIONS: Accelerated prestroke cognitive decline and poststroke cognitive decline were associated with incident stroke over a follow-up period of 12 years. Attention should be paid to the long-term cognitive problems of stroke survivors, and intervention and management of major vascular risk factors should start from early life or midlife to reduce the risk of cerebrovascular disease and the associated cognitive impairment.