The invention provides an aluminum alloy side wall structure and an automobile, belonging to the automobile lightweight field. The structure comprises an outer frame upper side beam, an outer frame Acolumn, an outer frame C column, an outer frame lower middle side beam, an outer frame lower front side beam, an outer frame lower rear side beam, an upper cross member, a lower cross member, a middlecross member, a door inclined beam, a plurality of upright columns and an inner plug-in joint. The structure comprises an outer frame upper side beam, an outer frame A column, an outer frame C column, an outer frame lower middle side beam, an outer frame lower front side beam, an outer frame lower rear side beam, a lower middle side beam of the outer frame, a lower front side beam of the outer frame, and a lower rear side beam of the outer frame by mortise and tenon. The top cross member is connected with the A column of the outer frame, and the end intersection of the C column of the outer frame is connected with the tenon and mortise of the plug-in joint. One end of the lower cross member is connected with the door inclined beam by the tenon and mortise joint, and the other end of the lower cross member is connected with the tenon and mortise joint of the C column of the outer frame by the tenon and mortise joint. The front beam under the outer frame is connected with the A column of the outer frame, the A column of the outer frame is connected with the upper beam of the outer frame, the upper beam of the outer frame is connected with the C column of the outer frame, and the C column of the outer frame is connected with the lower rear beam of the outer frame by means of plug-in joints. The automobile include that above structure. The structure and the lightweight effect of the automobile are good.