The invention relates to the field of automobile external decoration members and concretely relates to an automobile wheel cover external connection plate comprising an external decoration plate and awelding rack. The welding rack is arranged on the back surface of the external decoration plate; the welding rack is connected with the external decoration plate via a supersonic welding way; a plurality of supersonic welding points are formed on the welding rack; the supersonic welding points are alternately arranged on the welding rack; one part of the supersonic welding points are arranged onthe edge of the welding rack; and the supersonic points on the edge of the welding rack are tangent to the welding rack edge. The automobile wheel cover external connection plate is divided into two parts and the two parts are connected via the supersonic welding way, so a traditional one-time injection moulding way is changed, shrinkage of the automobile wheel cover external connection plate canbe avoided, and forming quality can be guaranteed; the automobile wheel cover external connection plate can be more beautiful and has great practicality; with the welding points on the welding rack edge, the whole welding rack surface can be connected with the external decoration plate, so warpage of the welding rack edge can be prevented.