Aiming to study slope collapse in Guanqiao-Longmen (Anxi), Hetian (Changting), Dapu-Penghu (Yongchun) and Guanpo (Zhaoan), Fujian Province, this paper discusses geologic and geomorphologic background for slope collapse erosion based on rock characteristics, geological structure and history of geology. Results show that in the areas over which slope collapse is most widely dist ributed, rock is characterized by neat int ruded rock (granite) in the later period of Yanshan, which is located in the regional rift zone being active from the Paleozoic Era. The developed landform is in a phase from late mature stage to old stage. Altitude and relative eroded datum plane jointly affect the development of slope collapse, and slope collapse mainly takes place in the areas where relative height is 20～100 m.