1. An x-ray fluoroscopic device, comprising: an X-ray tube and an X-ray detector that detects an X-ray that is irradiated from said X-ray tube and passes through a subject, wherein said X-ray fluoroscopic device specifies the position of a marker or a specific region by collecting images including said marker indwelled inside said subject's body or the specific region of said subject; said X-ray fluoroscopic device, further comprising: a template image memory element that stores the image including said marker or said specific region as a template image; a template matching element that specifies the position of the marker or the specific region relative to the continuously collected images by performing template matching utilizing the template image stored in the template image memory element relative to the continuously collected images, and a template clipping element that clips the image including said marker or said specific region specified by said template matching element as a template image and lets the template image memory element store said template image; and wherein said template matching element performs the template matching repeatedly during an X-ray fluoroscopy, in which a present image is compared to said template image that is clipped from the image collected prior to collection of the present image thereof and stored in said template image memory element, relative to the images continuously collected by the X-ray fluoroscopy.