In this paper, the 3D model of the human body is drawn, and the 3D transformation in the 3D garment piece design is realized by using the inverse mapping of 2D screen coordinates to 3D model coordinates. Then, the technique of virtual presentation of traditional ethnic clothing is studied, alternating the left and in-eye views and using the overlap of calculation to optimize the calculation to achieve a three-dimensional display. The virtual design and presentation effects of traditional ethnic costumes were assessed through a comprehensive comparison, sensory experience, interactive experience, emotional experience, and cognitive experience. The results showed that the regression coefficients of cognitive experience, sensory experience, interactive experience, and emotional experience of the virtual design and presentation of costumes were 0.98, 0.875, 0.993, and 0.996, respectively, which were 0.506, 0.36, 0.11, 0.161, and 0.048 more than the regression coefficients of the traditional display method in each dimension. This study provides the theoretical basis for combining traditional costumes with virtual technology.