In order to investigate the characters of inner ear vessels using the microvascular corrosion casting technique and scanning electron microscope the three-dimensional spatial picture of the vessels in cochlear basilar membrane, utriculus, sacculus and three ampullae of guinea pig were observed. It was found that arteriole coils were present in the modiolus ampullae, utriculus and sacculus. The length of arterioles was therefore prolonged and could keep the blood supply in inner ear stable. The possibility of blood coagulation in these segments increased because the blood flow became slower here. Another character was that the capillary networks appeared denser in stria vascularis and central part of the crista, whereas the vessel meshes in basilar membrane of cochlea and in planum semiculatum of ampullae were looser. These findings suggested that the metabolism in stria vascularis and central part of the crista would be more prosperous than that in the basilar membrane and planum semiculatum of ampullae.