The invention discloses a method and system for tracking a first arrival wave ray of an anisotropic medium. The method can comprise the steps: obtaining a phase angle based on a group angle; obtaininga group speed based on the phase angle; obtaining an initial travel time based on the group speed; obtaining the ray width based on ray data; and obtaining model travel time based on the initial travel time and ray width. The method enables the ray to be expanded into a ray with a certain width, and can achieve the better simulation of the propagation phenomenon of a wave field in a real medium.