A simulation method related with the opening force of a front vehicle door after a vehicle frontal collision, the method comprising: selecting a design component (3, 4, 1b, 1c) and an interface component (1, 2, 5, 6) from vehicle components which affect the opening of the front door, the design component being a component that will be modified for changing the opening force of the front door after the vehicle frontal collision, and the interface component being a component that will not be modified for changing the opening force of the front door; a first simulation step in which deformations of the design component (3, 4, 1b, 1c) and the interface component (1, 2, 5, 6), which are caused in the vehicle frontal collision and affect the opening of the front door, are calculated by simulation using finite element simulation software; characterized in that a second simulation step in which the opening force of the front door after the vehicle frontal collision is calculated by simulation using the finite element simulation software; and in that the deformations of the design component (3, 4, 1b, 1c) and the interface component (1, 2, 5, 6) obtained in the first simulation step are used as initial geometric conditions of the design component (3, 4, 1b, 1c) and the interface component (1, 2, 5, 6) in the second simulation step; and in that the first simulation step is carried out after a vehicle frontal collision simulation, and the deformation of the interface component (1, 2, 5, 6) obtained in the vehicle frontal collision simulation is fixed and used as a boundary condition for calculating the deformation of the design component (3, 4, 1b, 1c) in the first simulation step. selecting a design component (3, 4, 1b, 1c) and an interface component (1, 2, 5, 6) from vehicle components which affect the opening of the front door, the design component being a component that will be modified for changing the opening force of the front door after the vehicle frontal collision, and the interface component being a component that will not be modified for changing the opening force of the front door; a first simulation step in which deformations of the design component (3, 4, 1b, 1c) and the interface component (1, 2, 5, 6), which are caused in the vehicle frontal collision and affect the opening of the front door, are calculated by simulation using finite element simulation software; characterized in that a second simulation step in which the opening force of the front door after the vehicle frontal collision is calculated by simulation using the finite element simulation software; and in that the deformations of the design component (3, 4, 1b, 1c) and the interface component (1, 2, 5, 6) obtained in the first simulation step are used as initial geometric conditions of the design component (3, 4, 1b, 1c) and the interface component (1, 2, 5, 6) in the second simulation step; and in that the first simulation step is carried out after a vehicle frontal collision simulation, and the deformation of the interface component (1, 2, 5, 6) obtained in the vehicle frontal collision simulation is fixed and used as a boundary condition for calculating the deformation of the design component (3, 4, 1b, 1c) in the first simulation step.