The invention discloses an indoor decoration design method based on BIM. The method comprises the following steps of S1, building a three-dimensional model through BIM software, wherein the three-dimensional model comprises a ceiling model, a floor model, a wall body model and furniture part, and giving a material corresponding to each three-dimensional model; S2, simulating to enter a construction site to carry out acceptance check, checking whether the design of each three-dimensional model is consistent with a design scheme or not, and adaptively adjusting a non-conformance term according to design requirements; S3, rendering a drawing of the three-dimensional model; and S4, outputting the drawing. According to the method, a problem can be found and the design scheme can be adjusted timely in a dynamic simulation process based on the BIM, and the construction drawing can also be correspondingly adjusted in a design scheme adjustment process, so that the situations of wrong modification, modification missing and the like can be avoided, and the two-way performance is achieved, and thus the modification time cost is directly saved; after all aspects of the design scheme based on the BIM are perfected, the problems of material waste and the like in construction are indirectly solved, so that the construction can be carried out rapidly and accurately.