Abstract: Limited by conditions of current computer hardware, rendering of 3D city buildings is very slow, or even only part of the model could be rendered. In order to address this problem, a fast rendering method for point cloud models of 3D city buildings is proposed in this paper. Firstly characteristics of 3D city buildings point cloud models are analyzed. Then point cloud models of 3D city buildings are pre-processed and point nodes are quantized and designed. Finally, reconstruction of 3D city buildings point cloud models is done, which includes visibility determination, complement of empty block on surface of buildings, filtration of noisy point and multi-level of detail rendering. Extensive experiments on massive building point cloud models are carried out to verify the validity of the proposed method. Compared to traditional methods, the proposed method can remarkably lighten the pressure on storage and transport of point cloud model. The computing speed is increased about 20% and the rendering effect is also improved.