[Problem] To provide a position information identification method used for accurately identifying the position and speed of a photographed subject. [Solution] A position information identification method comprises: a step for acquiring subject images 3 which are photographed by a surveillance camera 2 having predetermined distortion characteristics pertaining to distortion in a photographed image; a step for capturing a first scale plate image 42 which is equivalent to an image obtained when a first scale plate 4 having first scale marks 41 is photographed at a first distance X from the surveillance camera 2; a step for superimposing the first scale plate image 42 and one of the subject images 3 on each other; a step for measuring, by using the first scale marks 41 on the first scale plate image 42, an image size A of a first reference object 5 of a first predetermined size B which is shown in the subject images 3; and a step for calculating a first subject distance Y from the surveillance camera 2 to the fir
