Due to the complicated influences of the car door system, the closing comfort is difficult to evaluate in the design of the car door system. In order to solve the problem and increase the development efficiency, based on the work of the whole process and the law of energy conservation, this paper models the power and resistance work under the closing conditions of the door system, and focuses on the construction of the work by door gravity, door limiter, sealing force of the seal, air resistance inside the seal and air resistance inside the vehicle in particular, and designs a computational model of the door closing comfort. The use of the model will effectively guide the development of door system parameterization.