本文主要结合贵州山区的公路修建前期工作开展实例,分析二级公路扩改建工程的可行性运用,并从项目功能、交通量分析及预测、技术标准、建设方案、投资估算及工期安排等方面分析,突出在二级公路扩改建工程可行性研究中要注意的相关事项,为推动贵州山区公路建设带动地方经济发展提供详细的可行性研究。 This paper mainly analyzes the feasibility of the expansion and reconstruction project of Grade Two Highway combining with the preliminary work of highway construction in mountainous area of ​​Guizhou. From the aspects of project function, traffic volume analysis and prediction, technical standards, construction plan, investment estimation and construction schedule , Highlighting the relevant issues that should be paid attention to in the feasibility study of expansion and reconstruction of secondary roads and providing detailed feasibility studies for promoting the development of highway construction in mountainous areas of Guizhou in order to promote local economy.