Stroke，as an acute cerebrovascular disease，is characterised by high incidence，high recurrence rate，high disability rate， high mortality rate，and significant economic burden，posing an extremely serious threat to human life and health. Functional near - infrared spectroscopy（fNIRS），a non -invasive，portable，and electromagnetic interference - resistant optical brain imaging technique， has seen extensive application in neuroscience and clinical rehabilitation fields in recent years. Particularly in the neurological rehabilitation of stroke，fNIRS has provided substantial support for rehabilitation assessment，treatment optimization and neural mechanism research due to its unique advantages. This paper reviews the main applications，research progress，existing controversies， and future research directions of fNIRS in this field，aiming to provide a reference for the research and practice in neurological rehabilitation of stroke.