Traditional interior design methods lack immersive user interaction and are often limited by insufficient visualization capabilities, making it difficult for clients to fully comprehend design concepts. In order to address the limitations of traditional interior design solutions in terms of display and user interaction, the author proposes an augmented reality based virtual model room display and interaction system for interior design. The system combines real-time rendering, speech recognition, and multimodal interaction technology, allowing users to intuitively feel the spatial layout, material selection, and decorative style, and adjust and optimize them through voice or gestures. The research results indicate that in augmented reality environments, prolonged hovering and swinging of arms for interaction significantly increases user fatigue. In addition, in terms of comfort, the average scores of the two are 2 and 4 points respectively, which may be due to the fact that augmented reality technology allows users to interact in more natural postures without the need for significant gestures. In terms of acceptability score, the average score of augmented reality technology is higher than that of traditional gesture interaction methods, at 4 and 3 points respectively. This system can effectively reduce design communication costs, improve user participation and decision-making efficiency. In the future, the application of AR technology in the field of interior design will further develop towards intelligence and personalization, promoting the digital transformation of the industry.