With a library of Fuzhou city in Jiangxi Province as the experimental research area, by using unmanned aerial vehicle (UAV) tilt photogrammetry technology, an acquisition of the aerial image data of the research area according to the planned route thus can be achieved. A research has been conducted on the characteristics of image data acquired by UAV tilt photogrammetry technology and the accuracy of image data processing, with a three-dimensional model built by adopting key technologies, and using Smart3D Capture software. The experimental result shows UAV tilt photogrammetry technology meets the requirements of 3D digital city modeling.