To improve location identification, we employed layered model joint hypocenters determination (JHD) and double-difference earthquake location algorithm (hypoDD), three-dimensions velocity structure location (3DLOC), and three-dimensions velocity structure with stations corrections location (3DCOR) for the Rueyli, Taiwan, earthquake sequence. We found that the 3DCOR can greatly improve the location identification precision of the Rueyli earthquake sequence. The Rueyli mainshock was relocated to 23.510°N, 120.660°E at the depth of 5.6 km. The focal depth is significantly deeper than the original CWBSN value of 2.8 km. Using this new location, a first-motion fault-plane solution shows that this earthquake is a thrust event with strike N53°E, dip 42°E, and rake 121°. Based on the hypocentral distribution pattern ascertained after relocation and focal mechanism, the Rueyli earthquake was probably caused by faulting in the Tachienshan fault.