As the base of united planning system application, power grid planning research platform (PGPRP) is the first integrated platform system for transmission grid planning in China, which completes a large number of design research and technology reserves. Based on the review of PGPRP construction process, this paper summarized the construction experience of planning platform, proposed the principles that should be analyzed in the total design process, analyzed the key points of construction, forecasted the future development trend of PGPRP, and suggested recommendations for next step.