A method of limiting a closing force of a motorized opening on a sealing line of a motor vehicle includes the step of calculating the closing force at each instant in a displacement of the opening while closing. The closing force is calculated by a difference between a force applied to the opening when an edge of the opening is situated in an area of or squashes the sealing line and a force applied to the opening just before the edge of the opening penetrates into the area of or squashes the sealing line. The method further includes the step of stopping an electric motor driving the opening when the closing force reaches a constant predetermined value. The closing force can be limited regardless of the climatic conditions or the operating conditions of the motor vehicle.