Recent rapid advances in surveying and mapping technology can produce sophisticated digital surface models (DSM) in the forms of image and point cloud, which have great application potential to assist landslide investigations. Taking the landslides adjacent to the interface between slate and schist along a highway in southeastern Taiwan as examples, this study uses tools such as close-range photography, UAV-based photography, and ground-based light detecting and ranging (LiDAR) to produce DSMs and point cloud models to assist landslide investigation. The possible application of these advanced surveying and mapping technologies is also discussed. Research results show that the advantages of these advanced technologies include: refined landform variation analysis, assisting surface geological survey, assisting rock mass characterization and related engineering parameters evaluation, and quantifying collapse content through digital elevation model of difference (DoD), which can effectively assist landslide investigation.