The invention discloses an automobile body assembly control method. The method includes the following steps that the on-off state of a whole automobile power source and the opened-closed state of all automobile doors are detected; when the on-off state of the whole automobile power source is an off state, and the opened-closed state of all the automobile doors is a closed state, whether an automobile key is in an automobile or not is detected; if the automobile key is located in the automobile, automatic control over automobile body assemblies is relieved; if the automobile key is not located in the automobile, whether a passenger is in the automobile or not is detected; if the passenger is in the automobile, automatic control over the automobile body assemblies is relieved; and if no passenger is in the automobile, the working state of the automobile body assemblies is automatically controlled. The invention further provides an automobile body assembly control system. By the adoption of the technical scheme, the working state of the automobile body assemblies of the automobile is automatically adjusted, the driving experience of a user is improved, and when all the passengers leave the automobile, potential safety hazards caused by the fact that the automobile body assemblies are not adjusted are effectively avoided.