An embodiment of the present invention provides a method for storing trajectory. The method includes: mapping, based on a plurality of positions on a trajectory of an entity, the trajectory to at least one road segment in a road network; identifying an entry point and an exit point of one of the road segments, wherein the entry point is a point where the entity starts traveling along the road segment, and the exit point is a point where the entity ends traveling along the road segment; and storing data related to at least one of the entry point and the exit point, to store the road segment as a part of information of the trajectory.