In view of the current problems of single display form and poor interaction of intangible cultural heritage painting wave, a digital online display system of intangible cultural heritage painting is designed and realized based on mobile augmented reality technology. Taking the intangible cultural heritage protection of Dunhuang murals as an example, the main functional modules of the system cloud and mobile terminal are designed, a fast modeling method based on the combination of 3 D scanning and grid iteration and simplification is proposed, ORB-FV and optical flow tracking algorithm are adopted to realize online image recognition and tracking registration, and the system development is completed based on Unity3D. The test results show that the system not only meets the requirements of the authenticity and fluency of the mobile terminal enhanced display of the intangible cultural heritage products but also realizes the real-time interactive coloring display function after the model enhanced display, which enhances the interest and interactivity of the intangible cultural heritage protection and dissemination. Through the research on the digital display of intangible cultural heritage painting of artificial intelligence technology, and the verification in the experiment, this topic found that the display of intangible cultural heritage painting art in the digital age can present a variety of inheritance methods, which also marks the intangible cultural heritage painting exhibition towards a new direction. Using the cell dynamics model of biomechanics, the impact of digital display on user visual interaction is explored, thereby enhancing the audience’s immersion and understanding of intangible cultural heritage paintings.