By employing the method of using space as a substitute for time, we studied the characteristics of canopy structure and dynamic changes of forest communities at different restoration/ succession stages of degraded Karst forest, namely, shrub stage, shrub-tree stage, tree stage and climax stage, using a CI -110 Plant Canopy Imager. The results show that: 1) Among the changes of forest canopy structure in different succession stages, leaf area index ranged between 1.56 and 2.92, and its value initially decreased and then increased from shrub stage to top climax stage, and only at tree stage did it achieve extremely significant differences with that of other stages. 2) There were no significant differences in the variations of mean leaf angle at different succession stages. 3) The variations of canopy gaps were not significant among the shrub stage, the shrub-tree stage, and the climax stage. It reached the maximum value at the tree stage, and there existed extremely significant differences between the tree stage and other succession stages. 4) The correlation analysis of several indexes of canopy structure showed that there was a highly significant, negative correlation between leaf area index and canopy gap.