<p>The detailed 3D fault model and further seismic rupture behavior analysis and fault mechanics simulation based on it are important and meaningful. A strong Mw 6.6 earthquake occurred in Luding, Sichuan, on 5 September 2022, the epicenter was located near the Y-shaped junction of the Xianshuihe Fault Zone (XSHF), the Longmen Shan Fault Zone (LMSF), and the Anninghe Fault Zone (ANHF). To date, a detailed 3D fault model has not been established for this earthquake, preventing a 3D Coulomb stress change (ΔCFS) calculation for further seismic potential analysis. Therefore, first we build a detailed 3D fault model of the earthquake and then we compute ΔCFS in the surrounding areas. Based on 3D modeling technics, we establish a 3D model of the main faults using previously published relocated earthquake catalog and focal mechanism solutions; including the Moxi segment (f₁) of the XSHF, the Daduhe fault (f₂) and two previously unknown faults (f₃ and f₄). The 3D ΔCFS indicates that the strike-slip mainshock of the Luding earthquake significantly triggered two M &gt; 5 dip-slip aftershocks. Moreover, it caused a remarkable increase in ΔCFS and hence a notable enhancement in seismic hazard in the northern ANHF.</p>