Abstract: Based on the investigation research of weathering characteristics and affecting factors of weathering action on surrounding rock of the Longmen cavern, Luoyang, it is pointed that the main forms of weathering action are biological weathering and physical weathering. And the weathering meachanism is also studied. With the growing of plants on the top of the mountain, the primary effecting factor of weathering damage has beening changed into biological weathering from previous physical weathering. The biological weathering damage include mainly the mechanical damage of plant rootsystem and the biological-chemical damage of plant humic compounds. So the damage of biological weathering action should be paid more attention.

Key words: Surrounding rock in cavern area, weathering form, affecting factor, weathering meachanism, weathering damage