An object of the present invention is to continuously display a series of images of the inside of the subject until the intra-body indwelling capsule is placed at the desired site in the subject, and to easily place the intra-body indwelling capsule endoscope at the desired site. The intra-subject indwelling system 1 according to the present invention includes an endoscope device 14 for imaging a first image of the inside of the subject an intra-body indwelling capsule 2, for imaging a second image of the inside of the subject a monitor device 12 for receiving the second image a receiving device 13, a monitor 11 for displaying the first image or the second image and an image switching device 10. The intra-body indwelling capsule 2 is arranged at the distal end of the inserting unit 5, and the separation from the inserting unit 5 is detected and the separation detection result is transmitted. The receiving device 13 receives the separation detection result. The image switching device 10 receives the first image from the endoscope device 14 and the second image from the monitor device 12, and switches the display image of the monitor 11 from the second image to the first image when receiving the separation detection result from the receiving device 13.