The invention relates to a typical daily load characteristics based substation locating method and a substation locating device. The method includes the following steps: acquiring geographic information of each load plot in a planning park; making analysis on load characteristics in the planning park, and calculating coordinates of a load center of the planning park at any moment; determining an optimal site confidence region of the substation of the planning park; determining a new substation site according to the optimal site confidence region of the substation. The device comprises a geographic information acquisition module, a load characteristics analysis and load center coordinate calculation module, an optimal site confidence region determination module and a new substation site determination module. The design is rational, the method and the device are oriented to large parks or urban areas such as industrial parks, large-scale commercial areas and residential areas, the optimal confidence region of the new site location economically optimal can be obtained, demands on substation functions and cost are met, and best power supply service is provided to the planning area.