Abstract: Kunming Changshui International Airport is located in Dabanqiao Street，Guandu District，Kunming City，Yunnan Province，with complex geographical environment，where its southern part is mainly karst geologic of plateau type，and the northern part is tectonic erosion hills and piedmont alluvial fans.Taking a extension project of this region as an example，we studied the distribution characteristics and development regularity of karst.Through qualitative analysis and theoretical calculation，the karst stability of the expansion site was preliminarily evaluated，and relevant suggestions were made based on empirical judgment.Finally，the suitability of engineering construction in the research area was evaluated.The results show that the possibility of karst collapse in the area is small，and most of the areas are basically stable，only some areas need special treatment，and 86.3% of the research area is suitable for the expansion project.The research results can provide basis for project feasibility research.