In this paper we calculate the ray-path and traveltimes of seismic wave with vector ray tracing, and then develop a technique to reconstruct the velocity image of acoustic media from direct traveltimes of crosswell data. The image of seismic velocity with a typical and complex geological model was present, which demonstrates the quickness and high precision of the rebuilding technique with crosswell data. In this paper we calculate the ray-path and traveltimes of seismic wave with vector ray tracing, and then develop a technique to reconstruct the velocity image of acoustic media from direct traveltimes of crosswell data. The image of seismic velocity with a typical and complex geological model was present, which demonstrates the quickness and high precision of the rebuilding technique with crosswell data.