The invention discloses a planning big data management and control system of a smart power distribution network and a method. The system comprises that a data layer constructs a global power network planning model; a basic data dictionary containing power network devices, graph standards and power network operation information is built; an application layer carries out statistic analysis and real time load actual measurement analysis to the power network devices and power network operation states in a set region; automatic filling of power network load data graphs, intelligent operation of planning data, intelligent verification of the planning data and intelligent statistics and summary of the planning data are realized; a service layer selects planning power network schemes; a display layer carries out centralized display, share and information issue to the planning and design achievement. According to the system and the method of the invention, through taking multi-source massive data such as basic geographic information, power network space and attribute thematic information and power network operation real time information as cores, planning and design data resources in the system are effectively integrated, a power network planning and design integrated information platform is built, and power network planning and design information-based foundation is tamped.