Abstract: Based on the amount of samples data with 5 factors such as community type,arbor and shrub coverage,biomass, community height and litter amounts using methods of principle components analysis and clustering analysis, the results indicated that the forming process of rocky desertification could be divided into 4 stages: initial stage,mid-stage,last stage and the end stage. Analyses on forming process and stage characters showed that the main reason of land system degraded in forming process of rocky desertification was degradation of vegetation sub-system, caused by human disturbance on the degradation of soil sub-system and micro-climate environment sub-system. A positive feedback was formed of mutual cycle and interaction among each sub-system. The degradation and losing of land productivity were essential of rocky desertification forming process.