The vasculature of the chinchilla cochlea was demonstrated with injected Prussian blue contrast. By and large, the vascular pattern is similar to other mammals. The vasculature appears to be richly developed, but separate types of vessels appear to be of small caliber. Particular findings for the chinchilla cochlea were the veins of the scala tympani, formed by a merging of collecting venules, running parallel to the spiral modiolar vein. Furthermore, no vessel of the basilar membrane under the tunnel of Corti was found, and which, when present, is of such great presumed importance for the oxygen supply to the organ of Corti. The scala vestibuli wall appears to be supplied completely arterially, in contrast with that of other mammals. The stria vascularis is broad and well developed, both at the apex and at the basal end.