Backgrounds: B-Flow imaging is the novel ultrasound technology which allows B-mode echogram to visualize blood flow on it. This image is basically produced by enhancing faint echoes from red blood cells and enables real-time visualization of blood flow on B-mode image. We are reporting some cases in which the B-Flow imaging provides clinically useful information. Case 1: A 78-year-old men with severe stenosis of right internal carotid artery. Color Doppler imaging showed mosaic signals in the stenotic lesion, however it was difficult to identify endothelium of that portion. B-Flow imaging could visualize clear border between blood and vessels. Case 2: A 54-year-old woman with fibromuscular dysplasia. Irregular endothelium was observed in bilateral common carotid arteries. B-Flow imaging but color Doppler imaging showed spiral stenosis. Case 3: A 76-year-old men with left internal carotid artery stenosis. There was mobile small plaque on isoechoic plaque with high echoic spots, which could be detected as a mobile high echoic tissue by B-Flow imaging. Case 4: A 77-year-old men who had carotid endarterectomy of left internal carotid artery. B-Flow imaging revealed an intimal flap presenting as a mobile high echoic speckle. Case 5: A 82-year-old men who had carotid endarterectomy of left internal carotid artery. Intimal flap could be detected by only B-Flow imaging but conventional color Doppler imaging. Conclusions: B-Flow imaging provides clear visualization of vascular structure with high temporal and spatial resolution, and it becomes clinically useful tool for the assessment of carotid artery abnormalities.