In response to the current heavy construction task and tight construction period of pumped storage power stations, this study focuses on the construction period of the main project of large-scale pumped storage power stations, analyzes the influencing factors and their importance on the construction period of the main project, and based on field research and statistical analysis, constructs an explanatory structural model (ISM) of the influencing factors through the development of Boolean operation program code.The results indicate that terrain and landform conditions are important factors affecting the construction period. Specific schedule optimization measures have been proposed for different construction routes, including technical measures, organizational measures, management measures, and economic measures.