[Objective] The objective of this study is to analyze the spatial change of rock desertification in karst region in order to provide the scientific basis for reasonable planning and integrated contorl of decision making department.[Methods] The research was conducted in Panlong watershed located in Wenshan Prefecture, the south-eastern part of Yunnan Province. The map of rock desertification intensity was interpreted from the remote sensing images in 1990, 2002 and 2009. The topographic factors(altitude, grade and exposure) that influenced the spatial distribution of rock desertification were analyzed by using overlay analysis method.[Results] From 1990 to 2009, rock desertification in Panlong watershed showed a increasing trend, and the distribution of rock desertification varied remarkably at the spatial scale.[Conclusion] The changes of landscape pattern and the spatial distribution of rock desertification were significantly influenced by topographic factors.