Based on spatial analysis and statistical analysis methods, the spatial-temporal evolution process of rocky desertification in Bijie experimental area, in terms of change pattern, direction, and rate, was analyzed using 3-phase distribution maps, which were interpreted by the decision tree method from Landsat images in 2000, 2005 and 2010. In particular, the interchanges among different degrees of rocky desertification were investigated. The results are listed below. (1) From 2000 to 2010, the total area of rocky desertification first increased and then stabilized, indicating that the expansion of rocky desertification was controlled preliminarily. However, the rocky desertification in some areas was still worse, and the effects of prevention and control were not optimistic. (2) The change patterns of rocky desertification were mainly gradual change, followed sequentially by leaping change and returning change. (3) The change directions of rocky desertification included both forward (improvement) and backward (deterioration), but the areas of slight improvement and slight deterioration were both very large. The co-occurrence of destruction and treatment has not been changed. (4) The potential rocky desertification, though not included as rocky desertification, was not stable and could be easily transformed into rocky desertification. (5) The change rates of rocky desertification were divided into three types: transfer-in rate, transfer-out rate, and comprehensive transfer rate. The comprehensive transfer rate of moderate rocky desertification was the largest compared with other types of rocky desertification, and the newly-formed moderate rocky desertification mainly came from light and potential rocky desertification. (6) The spatial-temporal evolution process of rocky desertification was closely correlated with ecological environment construction and socioeconomic development. This study provides theoretical foundations for preservation of ecological environment and comprehensive treatment of rocky desertification.