Abstract: By analyzing the performance of viewpoint-independent and view-dependent terrain generation algorithm in 3D real time rendering, we find that the view-independent algorithm cannot achieve a high resolution ratio when the terrain model is established, causing a lack of scene fidelity. If a high resolution ratio is required, the view independent terrain generation algorithm must store a large amount of data, and take lots of time to complete model rendering. Therefore, based on the view-independent terrain generation algorithm, in order to improve the fidelity of 3D scenes, we propose an optimized view-dependent terrain generation algorithm. This algorithm focuses on terrain split, view accuracy calculation, observation view distance calculation, and terrain visibility trimming. In a terrain split, a binary triangle tree is used to split the terrain node and show the relationship between the adjacent nodes. In the view accuracy calculation, each terrain block must calculate the variance value of the node error in each frame. In observation view distance calculation, we calculate the distance between observation point and block in each frame. In the terrain visibility trimming, terrain blocks are outside of the field of vision with the calculation, and this area can be ignored in the process of rendering to reduce amount of computation. Setting rendering accuracy as the measurement, we analyze the performance of the optimized view-dependent terrain generation algorithm and viewpoint-independent algorithm with experiments. In addition, by setting the rendering efficiency as the measurement, we analyze the performance of the optimized view-dependent terrain generation algorithm and original algorithm, and generate a three dimension terrain model using the proposed optimization algorithm.