The invention discloses an image labeling method for intracranial vascular flow delay, which comprises the steps of 1, performing vessel dividing and delay time calculating; 2, calculating to obtain athree-dimensional video of vascular development; 3, quantifying, to be specific dividing a low perfusion region and an infarct core region through dynamic perfusion data, finding parts in the low perfusion region, and counting to obtain an quantified value of flow delay in the low perfusion region. Intracranial vessels in the dynamic perfusion data are quantitatively labeled according to arrivaltime delay of a contrast agent based on the dynamic cranial perfusion image data of magnetic resonance or computed tomography; the delay time is subjected to color mode encoding and is subjected fusion displaying with structure images; obtained images can act as intermediate results to provide references for doctors to estimate and judge establishment degree and establishment passage of collateralcirculation. The invention also discloses an image labeling system for intracranial vascular flow delay.