BACKGROUND Intraoperative ultrasonography is widely used in neurosurgery for the management of intracerebral hematoma and brain tumor. However, the clinical value of this method in the surgery of cerebral arteriovenous malformations (AVMs) has not been reported. In this study, the application of intraoperative ultrasonography for AVM surgery was evaluated prospectively. METHODS This prospective clinical study comprised 41 patients who underwent microsurgical resection of cerebral AVMs at our institute. After routine craniotomy, ultrasonographic imaging with color Doppler ultrasonography and real-time contrast-enhanced ultrasonographic angiography if necessary were applied as navigated images on the monitor during the operation. RESULTS Ultrasonographic imaging made it easier to understand the vascular architecture during the operation. Color Doppler flow imaging clearly delineated the shape and margin of the AVMs. Intraoperative real-time contrast-enhanced ultrasonographic angiography enabled the surgeons to categorically identify AVM feeders both on the surface and deep in the tissue. CONCLUSIONS Microneurosurgery with intraoperative ultrasonographic image guidance was a safe, effective, and reliable method for identifying the afferent and efferent vessels and for confirming the complete resection of AVMs. These benefits of image-guided microsurgery were mostly apparent for deep-seated AVMs that were not visible on the surface of the brain.