To provide sense of immersion and quick real time interaction with users, key idea of level of detail (LoD) is adopted in Dalian nationalities university 3D walkthrough system. In 3D walkthrough system running on a common computer with limited memories and computing resources, rendering efficiency depends on refreshment rates of all rendering information including vertices, faces, texture data, especially texture data due to great proportion of about 30％ to 60％ among all data. Based on wavelet transform, multi-resolution representation of texture data or building images provides a simple hierarchical framework for interpreting the images information, which is used as multiple levels of detail for the same scene at interactive speeds. Here, view dependent LoD rendering framework is used to accelerate rendering of complex scenes. Real application of the proposed approach shows it not only reduces rendering complexities of the scenes with adoption of LoD models, but also makes full use of powerful multi-resolution representations of wavelet transform for images, thus gets real time interaction speeds for 3D walkthrough system.