To accurately assess the sensitivity of the parallelcomplex disaster in the Guangdong-Hong Kong-Macao Greater Bay Area, a sensitivity assessment index system for the parallel complex disaster of landslide and avalanche was constructed. Additionally, a sensitivity assessment model considering the spatial dimension superposition effect of the parallelcomplex disaster was established and derived. The results show that the parallel complex disaster of landslide and avalanche in the Guangdong-Hong Kong-Macao Greater Bay Area has high sensitivity areas concentrated in the northwestern part of the Bay Area such as Huaiji County and Fengkai County and the northeastern part of the Bay Area such as Longgang District and Huicheng District; low sensitivity areas are concentrated in the central part of the Bay Area such as Sanshui District and Nanhai District and the southwestern part of the Bay Area such as Taishan City and Enping City. Moreover, the higher sensitivity, middle sensitivity, and lower sensitivity areas are scattered sporadically between high and low sensitivity areas as transition areas.