In order to analyze, by a finite element method, the wiring property of a wire harness having a base end constrained and a distal end having a connector constrained to a connector base, a screen of a display unit displays a virtual three-dimensional shape image of the wire harness including the connector, using CAD data formed for designing the three-dimensional wiring shape and a condition setting screen for setting one part of analysis conditions, which is not included in the CAD data, of the property, the shape, a constraining position, and a constraining direction of the wire harness by input operation. The position on the moving destination of the connector, designated on the virtual three-dimensional shape image, is recognized as a coordinate value of the constraining position. The wiring shape of the wire harness and the reactive force upon grasping the connector by the FEM are analyzed under the analysis condition included in the CAD data, the analysis condition set on the condition setting screen, and the analysis condition necessary for estimating the constraining position prescribed by the coordinate value. The analysis of the virtual three-dimensional shape image of the analyzed wiring shape including the connector and of the reactive force is displayed on the screen.