The invention discloses a method for converting a land slide surface inclination angle to displacement and relates to a land slide monitoring and early warning technology. According to topographic and geologic conditions of typical land slide disasters, land slide in-situ model experiments and monitoring and actual measurement data are used as a foundation, and the method for converting the land slide surface inclination angle to the displacement is put forward via a relation between an earth surface inclination angle and an actual displacement amount during simulation of repeated damages caused on a slope by anthropogenic rainfall; based on specific monitoring data, monitoring information feedback can be given in time; a conversion formula is verified and corrected, and a finally a method for converting a land slide earth surface clinometer inclination angle to displacement is provided. According to the method for converting the land slide surface inclination angle to the displacement, an experience formula for converting the inclination angle into the displacement is provided, insufficient knowledge of a monitored earth surface inclination angle of a land slide and the actual displacement amount of the land slide can be compensated, and a scientific guarantee can be provided for a technical decision for geological disaster monitoring and comprehensive early warning.