Stroke is a leading cause of death and disability in adults worldwide. Although advancements in stroke treatment have significantly reduced mortality and disability rates, post-stroke cognitive impairment (PSCI) remains a common complication that severely impacts patients’quality of life. PSCI is characterized by impairments in memory, abstract thinking, visuospatial abilities, and personality changes, and is closely linked to survival rates. Despite extensive research aimed at identifying early warning biomarkers for PSCI, these findings have not yet been translated into clinical practice, potentially causing patients to miss optimal treatment windows. Therefore, early identification and intervention of PSCI should become an integral part of stroke management. This review summarizes the latest research progress on PSCI, discussing the potential of imaging tests, fluid biomarkers, and neurological function assessments. Future research should focus on combining imaging with artificial intelligence to identify cognitive impairment risks at an early stage, explore precise diagnostic indicators, and develop clinically applicable PSCI risk prediction models. Promoting early warning, early diagnosis, and early treatment will provide new ideas for the clinical management of PSCI.