In order to explore the role of digital intelligence technology in the protection and inheritance of intangible cultural heritage of ethnic costumes in the new era, the style, structure and data collection of Mongolia costumes are conducted based on DB 15/T 506-2012“Mongolian Tribal Costumes”. Taking Balhu women's as an example, CLO3D software is used to to carry out the 3D virtual restoration design and practice of national costumes from the aspects of virtual model selection, 2D plate production, virtual stitching and simulation, clothing pattern and fabric application, and clothing virtual display. The results show that CLO3D digital technology can efficiently and accurately restore the overall appearance of national costumes, and carry out three-dimensional display of the shape, color, pattern, accessories and other aspects of clothing culture, which is an effective method for the protection and inheritance of intangible cultural heritage national costumes.