For long-span bridges on gorge terrain, the determination of wind characteristics prevailing at bridge deck level may be a challenge. In this paper, a large bound of topography at bridge site was first obtained in Google Map. Then altitude data on discrete points of interest was extracted by Autocad. Finally, Imageware was employed to form a terrain surface. With a computational domain built with the terrain surface included, the wind field at the bridge site was numerically simulated with Reynolds-Averaged Navier-Stokes equations and the standard turbulence model. Considering different incoming wind conditions, wind characteristics on the bridge site, such as wind profile, angle of attack, as well as yaw angle along the bridge axis were determined. Also, the wind flow along the gorge can be visualized, which provided a direct insight for wind environment. The present method provides an effective approach for wind parameters on a wide range of complex terrains.