Accurate prediction of coseismic landslides is essential for understanding geological disaster systems, strengthening infrastructure, and protecting human lives and property. This paper proposes a spectral element method-Newmark (SEM-Newmark) coupling framework that considers the source rupture mode of conjugate faults. The fault rupture mechanism and wave field propagation process of Yunnan's 2014 Ludian Mw6.1 earthquake are reproduced. The simulated cut-off frequency is 4 Hz. The peak ground acceleration (PGA) in east-west, north-south, and vertical directions at the observation points are 9.35, 7.71, and 4.78 m/s2, respectively, showing strong consistency with the recorded values of the station. By integrating more comprehensive ground motion parameters, the SEM-Newmark permanent displacement prediction model is developed, demonstrating high accuracy in fitting the relationship between the acceleration ratio and permanent displacement (AR-lgDN) change. The high-risk regions of coseismic landslide disasters are primarily distributed along the strike of seismogenic faults, exhibiting the near-fault amplification effect and directional effect. Additionally, the spatial distribution characteristics and the amount of coseismic landslides, based on SEM-Newmark permanent displacement interpretation, align with the results from the remote sensing compilation. This research provides a reliable new approach for assessing, identifying, and cataloging coseismic disasters in complex regions.