The living raccoon, Procyon lotor, is a highly adaptable species inhabiting much of North America. Its evolutionary history, however, is poorly known due to a dearth of fossil records, especially pre-Pleistocene records. We describe a new species, Procyon garberi, from the late Miocene (late Hemphillian; approximately 6.4–6.2 Ma) Modesto Reservoir Member of the Mehrten Formation in the Modesto Reservoir area, Stanislaus County, California. This new species is relatively small among known species Procyon, and possesses primitive dental morphology, such as unwidened premolars, poorly developed posterior accessory cusp on p4, principal cusps in trigonid of m1 forming a high angle of 75-78°, and relatively long m2. However, limited and fragmentary materials from the Mehrten Formation make evaluations of the variations difficult in light of considerable size variations in living raccoon. Despite these difficulties, if we take the current fossil record at its face value, California has the earliest (late Miocene) and likely most primitive species in the form of P. garberi, followed by P. rexroadensis from the Pliocene (middle Blancan) of Kansas and Texas that has reached the living raccoon grade in dental morphology, followed by two species, P. gipsoni and P. megalokolos, in the early Pleistocene (late Blancan) of Florida, and by middle to late Pleistocene (Irvingtonian and Rancholabrean), P. lotor had emerged.