The invention relates to the field of cars, and in particular relates to a method for controlling error-locking of a mechanical door lock with a car key inside. The method comprises the steps of sending a mechanical door locking signal to a car body controller through a mechanical door lock state switch when locking the mechanical door of the car; sending a car key state detection instruction to an IMMO (Immobiliser) coil at the car through the car body controller while controlling to lock the mechanical door; feeding back the detection result to the car body controller through the IMMO coil; controlling whether the mechanical door is unlocked by the car body controller according to the state of the car key. With the adoption of the method, a user does not need to remove the key in case of going out for a short time, which facilitates the users without bags, and the key can be prevented from.