A cable connector assembly includes a butt joint, a flat cable electrically connected with the butt joint directly, a pressing ring connected to the outer side of the cable in a pressed manner, an inner mold wrapping a part of the butt joint and all the pressing ring and a metal housing arranged on the outer side of the inner mold. The cable includes a plurality of core wires and an outer coatinglayer coating the core wires. Each core wire includes a conductor. The wire cores include first core wires having comparatively larger conductor diameter and second core wires having comparatively smaller conductor diameter. The first core wires are naked leads. The conductors of the first core wires are wrapped by the outer coating layer directly. Each second core wire includes an insulation layer coating the corresponding conductor. The structure of the flat cable is thin, so that thickness reduction of the cable connector assembly is promoted.