Abstract: The frequent occurred landslides in the clastic rock is a common geohazard in Guangxi’s tropical humid environment. Based on the site geological investigation and geotechnical exploration results, a longterm slope deformation monitoring was developed by installing the inclinometers, magnetic extensometers and groundwater monitoring device at various locations of a sliding slope. The sliding surface was identified throughout the deformation of the inclinometers. The deformationfailure mechanism was able to be developed. It is recognized that the landslide in the clastic rock slopes is strongly affected by the heavy precipitation and human activities. The tectonic structure of the slope is also contributed to the landslide hazards.

Key words: tropical humid environment, clastic rock, landslide, slope inclinometers, deformation monitoring