Interior design, as a highly practical subject, is a new design concepts. It is the application of new teaching methods and the expression of new design elements which make the teaching continuously optimized and adaptable to the development of today’s interior design industry and talents cultivation. Three-dimensional (3D) computer-aided simulation is a technology that uses computer-related software to design, express, generate, process, and display 3D graphics. The application of this technology to interior design teaching program enables students to have an intuitive experience of space volume, material, proportion, color and other aspects and preview the design effect, thereby greatly improving classroom efficiency. Therefore, on the basis of summarizing and analyzing previous research works, this paper first expounded the research status and significance of interior design teaching optimization, elaborated the development background, current status and future challenges of 3D computer-aided simulation, then proposed the curriculum construction optimization of interior design based on 3D computer-aided simulation including strategic optimization and structural optimization. Through the analysis of the teaching practice optimization of interior design based on 3D computer-aided simulation including teaching system optimization and practice system optimization, the paper discussed the teaching optimization mode and its realization paths of interior design based on 3D computer-aided simulation. Finally, the paper provided a reference for the further researches on teaching optimization of interior design based on 3D computer-aided simulation. © 2021 CAD Solutions, LLC.