As a common category of ischemic stroke， branch atheromatous disease （BAD） always manifests as progressive motor deficiency and early neurological deterioration. There is a lack of early identification means of BAD currently. This article mainly reviews the research progress of early diagnosis of BAD from the perspectives of peripheral blood biology and imaging markers， which helps deepen clinical physicians' understanding of the disease and provides important assistance for its early prevention， treatment， and improvement of patient prognosis.